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  • Preventing SQL injecting in a database class

    - by Josh
    I'm building a database class and thought it'd be a good idea to incorporate some form of SQL injection prevention (duh!). Here's the method that runs a database query: class DB { var $db_host = 'localhost'; var $db_user = 'root'; var $db_passwd = ''; var $db_name = 'whatever'; function query($sql) { $this->result = mysql_query($sql, $this->link); if(!$this->result) { $this->error(mysql_error()); } else { return $this->result; } } } There's more in the class than that but I'm cutting it down just for this. The problem I'm facing is if I just use mysql_real_escape_string($sql, $this->link); then it escapes the entire query and leads to a SQL syntax error. How can I dynamically find the variables that need to be escaped? I want to avoid using mysql_real_escape_string() in my main code blocks, i'd rather have it in a function. Thanks.

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  • How can I write my code to attempt a database action but continue executing code on failure?

    - by Chris
    Simple question I guess, I want to use PHP to write an update to an existing row in my database, if it doesn't happen I want to log the failure but continue executing the code. While it would be nice to have records of failures to track down issues, that the update failed isn't that important to my user, nor will it affect the running of any other code; the query is simply for a 'cosmetic' but entirely unnecessary piece of information. My database class's query function is set to die on failure, could I modify that or is there another way of doing it without altering my standard query code?

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  • partial string matching - R

    - by DonDyck
    I need to write a query in R to match partial string in column names. I am looking for something similar to LIKE operator in SQL. For e.g, if I know beginning, middle or end part of the string I would write the query in format: LIKE 'beginning%middle%' in SQL and it would return matching strings. In pmatch or grep it seems I can only specify 'beginning' , 'end' and not the order. Is there any similar function in R that I am looking for? For example, say I am looking in the vector: y<- c("I am looking for a dog", "looking for a new dog", "a dog", "I am just looking") Lets say I want to write a query which picks "looking for a new dog" and I know start of the string is "looking" and end of string is "dog". If I do a grep("dog",y) it will return 1,2,3. Is there any way I can specify beginning and end in grep?

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  • Pass database data to multiples views-Laravel

    - by user3696018
    I have a database with details of daily sales. To query a database, I have a form in a view with parameters that will query as date of admission, client and others. The result is shown in another view with the daily details of income, and below is a summary of the article do all entered. The summary I wish to transfer to another view, try to view :: composer but only transfer the empty query (I saw it with debug bar). Just appeared an empty view. How I can transfer data from the database without the latter view is empty? The second html view is totaly diferent , only the data is the same.

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  • Why isn't INT more efficient than UNIQUEIDENTIFIER (according to the execution plan)?

    - by ck
    I have a parent table and child table where the columns that join them together are the UNIQUEIDENTIFIER type. The child table has a clustered index on the column that joins it to the parent table (its PK, which is also clustered). I have created a copy of both of these tables but changed the relationship columns to be INTs instead, have rebuilt the indexes so that they are essentially the same structure and can be queried in the same way. When I query for a known 20 records from the parent table, pulling in all the related records from the child tables, I get identical query costs across both, i.e. 50/50 cost for the batches. If this is true, then my giant project to change all of the tables like this appears to be pointless, other than speeding up inserts. Can anyone provide any light on the situation? EDIT: The question is not about which is more efficient, but why is the query execution plan showing both queries as having the same cost?

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  • Complex SQL queries (DELETE)?

    - by Joe
    Hello all, I'm working with three tables, and for simplicity's sake let's call them table A, B, and C. Both tables A and B have a column called id, as well as one other column, Aattribute and Battribute, respectively. Column c also has an id column, and two other columns which hold values for A.id and B.id. Now, in my code, I have easy access to values for both Aattribute and Battribute, and want to delete the row at C, so effectively I want to do something like this: DELETE FROM C WHERE aid=(SELECT id FROM A WHERE Aattribute='myvalue') AND bid=(SELECT id FROM B WHERE Battribute='myothervalue') But this obviously doesn't work. Is there any way to make a single complex query, or do I have to run three queries, where I first get the value of A.id using a SELECT with 'myvalue', then the same for B.id, then use those in the final query? [Edit: it's not letting me comment, so in response to the first comment on this: I tried the above query and it did not work, I figured it just wasn't syntactically correct. Using MS Access, for what it's worth. ]

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  • insert into select from other table

    - by user3815079
    I need to add multiple records based on data from another table where the event is the same. I've found on this forum insert into table2(id,name) select "001",first_name from table1 where table1.id="001" as possible solution for my question. So I thought this should be the following syntax: insert into reservations(event,seat) select "99",id from seats where seats.id>0 to add all seats to event 99. However when I run this query mysql gives the message 'MySQL returned an empty resultset (0 rows). (query 0.0028 sec)' and no records were added. I translated the message so could be sligthly different. When I only use the "select "99",id from seats where seats.id0" query, it returns me 1080 rows.

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  • Why delete and recreate a querydef object when you can just change the .SQL property?

    - by dblE
    Do you remember the venerable old Microsoft Query by Form (QBF) VBA example from back in the day link that recommended that you delete an existing query and then recreate it dynamically?: On Error Resume Next db.QueryDefs.Delete ("qryResults") On Error GoTo 0 Set qdf = db.CreateQueryDef("qryResults", "SELECT p.*... Why not just change the SQL property of the querydef object? qdf.SQL = "SELECT p.*... I am wondering if anyone knows why the MS engineers wrote an example that suggests that you delete and then recreate a query instead of simply changing the SQL property? I would guess that the act of deleting and recreating objects over time could contribute to corruption and bloating in your front end, not to mention changing the SQL property is so much simpler. Does anyone have more insight into this?

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  • PHP - if == not working for 0 or ""

    - by user2933212
    I am checking the validation of the request with an if query, if ($request_userid == $userid) { ... } Thats working as expected. But further testing has shown, that if $request_userid or $userid is 0 or "", then the condition is true and the script runs the if query but it shouldn't. I am currently solving it with: if ($userid == "" ) { exit ("exit"); } But I don't think that this is the right way? Can you explain why it doesn’t work with the if query and what would be the correct way to check it?

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  • SQLite delete the last 25% of records in a database.

    - by Steven smethurst
    I am using a SQLite database to store values from a data logger. The data logger will eventually fills up all the available hard drive space on the computer. I'm looking for a way to remove the last 25% of the logs from the database once it reaches a certain limit. Using the following code: $ret = Query( 'SELECT id as last FROM data ORDER BY id desc LIMIT 1 ;' ); $last_id = $ret[0]['last'] ; $ret = Query( 'SELECT count( * ) as total FROM data' ); $start_id = $last_id - $ret[0]['total'] * 0.75 ; Query( 'DELETE FROM data WHERE id < '. round( $start_id, 0 ) ); A journal file gets created next to the database that fills up the remaining space on the drive until the script fails. How/Can I stop this journal file from being created? Anyway to combined all three SQL queries in to one statement?

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  • MvcExtensions - PerRequestTask

    - by kazimanzurrashid
    In the previous post, we have seen the BootstrapperTask which executes when the application starts and ends, similarly there are times when we need to execute some custom logic when a request starts and ends. Usually, for this kind of scenario we create HttpModule and hook the begin and end request events. There is nothing wrong with this approach, except HttpModules are not at all IoC containers friendly, also defining the HttpModule execution order is bit cumbersome, you either have to modify the machine.config or clear the HttpModules and add it again in web.config. Instead, you can use the PerRequestTask which is very much container friendly as well as supports execution orders. Lets few examples where it can be used. Remove www Subdomain Lets say we want to remove the www subdomain, so that if anybody types http://www.mydomain.com it will automatically redirects to http://mydomain.com. public class RemoveWwwSubdomain : PerRequestTask { public RemoveWww() { Order = DefaultOrder - 1; } protected override TaskContinuation ExecuteCore(PerRequestExecutionContext executionContext) { const string Prefix = "http://www."; Check.Argument.IsNotNull(executionContext, "executionContext"); HttpContextBase httpContext = executionContext.HttpContext; string url = httpContext.Request.Url.ToString(); bool startsWith3W = url.StartsWith(Prefix, StringComparison.OrdinalIgnoreCase); bool shouldContinue = true; if (startsWith3W) { string newUrl = "http://" + url.Substring(Prefix.Length); HttpResponseBase response = httpContext.Response; response.StatusCode = (int)HttpStatusCode.MovedPermanently; response.Status = "301 Moved Permanently"; response.RedirectLocation = newUrl; response.SuppressContent = true; shouldContinue = false; } return shouldContinue ? TaskContinuation.Continue : TaskContinuation.Break; } } As you can see, first, we are setting the order so that we do not have to execute the remaining tasks of the chain when we are redirecting, next in the ExecuteCore, we checking the whether www is present, if present we are sending a permanently moved http status code and breaking the task execution chain otherwise we are continuing with the chain. Blocking IP Address Lets take another scenario, your application is hosted in a shared hosting environment where you do not have the permission to change the IIS setting and you want to block certain IP addresses from visiting your application. Lets say, you maintain a list of IP address in database/xml files which you want to block, you have a IBannedIPAddressRepository service which is used to match banned IP Address. public class BlockRestrictedIPAddress : PerRequestTask { protected override TaskContinuation ExecuteCore(PerRequestExecutionContext executionContext) { bool shouldContinue = true; HttpContextBase httpContext = executionContext.HttpContext; if (!httpContext.Request.IsLocal) { string ipAddress = httpContext.Request.UserHostAddress; HttpResponseBase httpResponse = httpContext.Response; if (executionContext.ServiceLocator.GetInstance<IBannedIPAddressRepository>().IsMatching(ipAddress)) { httpResponse.StatusCode = (int)HttpStatusCode.Forbidden; httpResponse.StatusDescription = "IPAddress blocked."; shouldContinue = false; } } return shouldContinue ? TaskContinuation.Continue : TaskContinuation.Break; } } Managing Database Session Now, let see how it can be used to manage NHibernate session, assuming that ISessionFactory of NHibernate is already registered in our container. public class ManageNHibernateSession : PerRequestTask { private ISession session; protected override TaskContinuation ExecuteCore(PerRequestExecutionContext executionContext) { ISessionFactory factory = executionContext.ServiceLocator.GetInstance<ISessionFactory>(); session = factory.OpenSession(); return TaskContinuation.Continue; } protected override void DisposeCore() { session.Close(); session.Dispose(); } } As you can see PerRequestTask can be used to execute small and precise tasks in the begin/end request, certainly if you want to execute other than begin/end request there is no other alternate of HttpModule. That’s it for today, in the next post, we will discuss about the Action Filters, so stay tuned.

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  • There are 2 jobs available - which one sounds better all round [closed]

    - by Steve Gates
    I am currently employed at a company where we scrape by each year breaking even, sometimes having a little profit. The development environment is very relaxed and we have a laugh. My colleagues are not interested in improving their knowledge unless they have to, so trying to get them to adopt things like TDD is a non-starter. My development manager is stuck in .Net 2 land and refuses to use things like LINQ. He over complicates architecture and writes very unreadable code, heres an example SortedList<int,<SortedList<int,SortedList<int, MyClass>>>> The MD of the company has no drive and lets the one sales guy bring in the contracts. We are not busy all the time and this allows me time to look at new technology and learn. In terms of using things like TDD, my development manager has no problem with it and can kind of see the purpose of it, he just wont use it himself. This means I am alone in learning new things and am often resorting to StackOverflow to make sure I get things right. The company has a lot of flexibility, I can work from home if needs be and when my daughter was born they let me work from home 1 day a week however they expect this flexibility in return often asking me to travel occasionally on a Friday afternoon for the following week. Sometimes its abroad. We are also pretty much on call 24/5 as we have engineers in various countries. Also we have no testers so most of the testing is done by us developers and some testing by engineers. Either way no-one likes testing! I have been offered a role at a company I worked at 5 years ago. They were quite Victorian in their working practices but it appears to have relaxed now although I suspect still reasonably formal. There is a new team of developers I don't know and they are about to move to new offices. The team lead is a guy that was there when I was and I get the impression he takes his role seriously and likes his formal procedures and documentation. I think some of the Victorian practices may have rubbed off on him. However he did say if things crop up then as long as I can trust the person they can work at home although he prefers people in the office. The team uses SCRUM, TDD and SOLID design principles so they are quite up to date in technology. They are reasonably Microsoft focused. It appears the Technical Director might be the R&D man and research new technology on his own not allowing developers to play with new technology. He possibly might be a super developer and makes all the decisions that no can argue with. They are currently moving to Entity Framework away from NHibernate based on issues that their queries seem to fail sometimes and they feel NHibernate is stagnant. They have analysts and a QA team. The MD is focused and they are an expanding company making profit each year. I'm not sure what the team morale is and whether they have a laugh. When I had a tour around the office they were there in dead silence. I'm really unsure which role is the best for me and going with my gut instinct is useless as I'm not sure what my gut is telling me. Based on the information above which role would you choose and why?

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  • How To Delete Top 100 Rows From SQL Server Tables

    - by Gopinath
    If you want to delete top 100/n records from an SQL Server table, it is very easy with the following query: DELETE FROM MyTable WHERE PK_Column IN(     SELECT TOP 100 PK_Column     FROM MyTable     ORDER BY creation    ) Why Would You Require To Delete Top 100 Records? I often delete a top n records of a table when number of rows in the are too huge. Lets say if I’ve 1000000000 records in a table, deleting 10000 rows at a time in a loop is faster than trying to delete all the 1000000000  at a time. What ever may be reason, if you ever come across a requirement of deleting a bunch of rows at a time, this query will be helpful to you. Join us on Facebook to read all our stories right inside your Facebook news feed.

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  • TFS 2008 Web Access Report 100 record limitation

    - by HosamKamel
    By default TFS 2008 Web Access has the limit of 100 record when you open any query in report mode. Even if you tried to export the query to excel or PDF you will only get first 100 record exported. To overcome this issue, you have to reconfigure this count in the web.config file Navigate to web access files C:\Program Files\Microsoft Visual Studio 2008 Team System Web Access\Wiwa Open web.config modify maxWorkitemsInReportList count to whatever count you need. You need to do modify the same configuration in web.config located here C:\Program Files\Microsoft Visual Studio 2008 Team System Web Access\Web  A full discussion thread exists here Team Foundation Server - Team System Web Access

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  • EBS: OPP Out of memory issue...

    - by ashish.shrivastava
    FO Processor is little more hungry for memory compare to other Java process. If XSLT scalable option is not set and the same time your RTF template is not well optimized definitely you are going to hit Out of memory exception while working with large volume of data. If the memory requirement is not too bad, you can set the OOP Heap size using following SQL queries. Check the current OPP JVM Heap size using following SQL query SQL select DEVELOPER_PARAMETERS from FND_CP_SERVICES where SERVICE_ID = (select MANAGER_TYPE from FND_CONCURRENT_QUEUES where CONCURRENT_QUEUE_NAME = 'FNDCPOPP' DEVELOPER_PARAMETERS ----------------------------------------------------- J:oracle.apps.fnd.cp.gsf.GSMServiceController:-mx512m Set the JVM Heap size using following SQL query SQL update FND_CP_SERVICES set DEVELOPER_PARAMETERS = 'J:oracle.apps.fnd.cp.gsf.GSMServiceController:-mx2048m' where SERVICE_ID = (select MANAGER_TYPE from FND_CONCURRENT_QUEUES where CONCURRENT_QUEUE_NAME = 'FNDCPOPP'); SQLCommit; . You need to restart the Concurrent Manager to make it effective. If this does not resolve the issue, You need to optimize RTF template and set the XSLT scalable option true.

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  • Using LogParser - part 2

    - by fatherjack
    PersonAddress.csv SalesOrderDetail.tsv In part 1 of this series we downloaded and installed LogParser and used it to list data from a csv file. That was a good start and in this article we are going to see the different ways we can stream data and choose whether a whole file is selected. We are also going to take a brief look at what file types we can interrogate. If we take the query from part 1 and add a value for the output parameter as -o:datagrid so that the query becomes LOGPARSER "SELECT top 15 * FROM C:\LP\person_address.csv" -o:datagrid and run that we get a different result. A pop-up dialog that lets us view the results in a resizable grid. Notice that because we didn't specify the columns we wanted returned by LogParser (we used SELECT *) is has added two columns to the recordset - filename and rownumber. This behaviour can be very useful as we will see in future parts of this series. You can click Next 10 rows or All rows or close the datagrid once you are finished reviewing the data. You may have noticed that the files that I am working with are different file types - one is a csv (comma separated values) and the other is a tsv (tab separated values). If you want to convert a file from one to another then LogParser makes it incredibly simple. Rather than using 'datagrid' as the value for the output parameter, use 'csv': logparser "SELECT SalesOrderID, SalesOrderDetailID, CarrierTrackingNumber, OrderQty, ProductID, SpecialOfferID, UnitPrice, UnitPriceDiscount, LineTotal, rowguid, ModifiedDate into C:\Sales_SalesOrderDetail.csv FROM C:\Sales_SalesOrderDetail.tsv" -i:tsv -o:csv Those familiar with SQL will not have to make a very big leap of faith to making adjustments to the above query to filter in/out records from the source file. Lets get all the records from the same file where the Order Quantity (OrderQty) is more than 25: logparser "SELECT SalesOrderID, SalesOrderDetailID, CarrierTrackingNumber, OrderQty, ProductID, SpecialOfferID, UnitPrice, UnitPriceDiscount, LineTotal, rowguid, ModifiedDate into C:\LP\Sales_SalesOrderDetailOver25.csv FROM C:\LP\Sales_SalesOrderDetail.tsv WHERE orderqty > 25" -i:tsv -o:csv Or we could find all those records where the Order Quantity is equal to 25 and output it to an xml file: logparser "SELECT SalesOrderID, SalesOrderDetailID, CarrierTrackingNumber, OrderQty, ProductID, SpecialOfferID, UnitPrice, UnitPriceDiscount, LineTotal, rowguid, ModifiedDate into C:\LP\Sales_SalesOrderDetailEq25.xml FROM C:\LP\Sales_SalesOrderDetail.tsv WHERE orderqty = 25" -i:tsv -o:xml All the standard comparison operators are to be found in LogParser; >, <, =, LIKE, BETWEEN, OR, NOT, AND. Input and Output file formats. LogParser has a pretty impressive list of file formats that it can parse and a good selection of output formats that will let you generate output in a format that is useable for whatever process or application you may be using. From any of these To any of these IISW3C: parses IIS log files in the W3C Extended Log File Format.   NAT: formats output records as readable tabulated columns. IIS: parses IIS log files in the Microsoft IIS Log File Format. CSV: formats output records as comma-separated values text. BIN: parses IIS log files in the Centralized Binary Log File Format. TSV: formats output records as tab-separated or space-separated values text. IISODBC: returns database records from the tables logged to by IIS when configured to log in the ODBC Log Format. XML: formats output records as XML documents. HTTPERR: parses HTTP error log files generated by Http.sys. W3C: formats output records in the W3C Extended Log File Format. URLSCAN: parses log files generated by the URLScan IIS filter. TPL: formats output records following user-defined templates. CSV: parses comma-separated values text files. IIS: formats output records in the Microsoft IIS Log File Format. TSV: parses tab-separated and space-separated values text files. SQL: uploads output records to a table in a SQL database. XML: parses XML text files. SYSLOG: sends output records to a Syslog server. W3C: parses text files in the W3C Extended Log File Format. DATAGRID: displays output records in a graphical user interface. NCSA: parses web server log files in the NCSA Common, Combined, and Extended Log File Formats. CHART: creates image files containing charts. TEXTLINE: returns lines from generic text files. TEXTWORD: returns words from generic text files. EVT: returns events from the Windows Event Log and from Event Log backup files (.evt files). FS: returns information on files and directories. REG: returns information on registry values. ADS: returns information on Active Directory objects. NETMON: parses network capture files created by NetMon. ETW: parses Enterprise Tracing for Windows trace log files and live sessions. COM: provides an interface to Custom Input Format COM Plugins. So, you can query data from any of the types on the left and really easily get it into a format where it is ready for analysis by other tools. To a DBA or network Administrator with an enquiring mind this is a treasure trove. In part 3 we will look at working with multiple sources and specifically outputting to SQL format. See you there!

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  • CQRS &ndash; Questions and Concerns

    - by Dylan Smith
    I’ve been doing a lot of learning on CQRS and Event Sourcing over the last little while and I have a number of questions that I haven’t been able to answer. 1. What is the benefit of CQRS when compared to a typical DDD architecture that uses Event Sourcing and properly captures intent and behavior via verb-based commands? (other than Scalability) 2. When using CQRS what do you do with complex query-based logic? I’m going to elaborate on #1 in this blog post and I’ll do a follow-up post on #2. I watched through Greg Young’s video on the business benefits of CQRS + Event Sourcing and first let me say that I thought it was an excellent presentation that really drives home a lot of the benefits to this approach to architecture (I watched it twice in a row I enjoyed it so much!). But it didn’t answer some of my questions fully (I wish I had been there to ask these of Greg in person!). So let me pick apart some of the points he makes and how they relate to my first question above. I’m completely sold on the idea of event sourcing and have a clear understanding of the benefits that it brings to the table, so I’m not going to question that. But you can use event sourcing without going to a CQRS architecture, so my main question is around the benefits of CQRS + Event Sourcing vs Event Sourcing + Typical DDD architecture Architecture with Event Sourcing + Commands on Left, CQRS on Right Greg talks about how the stereotypical architecture doesn’t support DDD, but is that only because his diagram shows DTO’s coming up from the client. If we use the same diagram but allow the client to send commands doesn’t that remove a lot of the arguments that Greg makes against the stereotypical architecture? We can now introduce verbs into the system. We can capture intent now (storing it still requires event sourcing, but you can implement event sourcing without doing CQRS) We can create a rich domain model (as opposed to an anemic domain model) Scalability is obviously a benefit that CQRS brings to the table, but like Greg says, very few of the systems we create truly need significant scalability Greg talks about the ability to scale your development efforts. He says CQRS allows you to split the system into 3 parts (Client, Domain/Commands, Reads) and assign 3 teams of developers to work on them in parallel; letting you scale your development efforts by 3x with nearly linear gains. But in the stereotypical architecture don’t you already have 2 separate modules that you can split your dev efforts between: The client that sends commands/queries and receives DTO’s, and the Domain which accepts commands/queries, and generates events/DTO’s. If this is true it’s not really a 3x scaling you achieve with CQRS but merely a 1.5x scaling which while great doesn’t sound nearly as dramatic (“I can do it with 10 devs in 12 months – let me hire 5 more and we can have it done in 8 months”). Making the Query side “stupid simple” such that you can assign junior developers (or even outsource it) sounds like a valid benefit, but I have some concerns over what you do with complex query-based logic/behavior. I’m going to go into more detail on this in a follow-up blog post shortly. He also seemed to focus on how “stupid-simple” it is doing queries against the de-normalized data store, but I imagine there is still significant complexity in the event handlers that interpret the events and apply them to the de-normalized tables. It sounds like Greg suggests that because we’re doing CQRS that allows us to apply Event Sourcing when we otherwise wouldn’t be able to (~33:30 in the video). I don’t believe this is true. I don’t see why you wouldn’t be able to apply Event Sourcing without separating out the Commands and Queries. The queries would just operate against the domain model instead of the database. But you’d still get the benefits of Event Sourcing. Without CQRS the queries would only be able to operate against the current state rather than the event history, but even in CQRS the domain behaviors can only operate against the current state and I don’t see that being a big limiting factor. If some query needs to operate against something that is not captured by the current state you would just have to update the domain model to capture that information (no different than if that statement were made about a Command under CQRS). Some of the benefits I do see being applicable are that your domain model might end up being simpler/smaller since it only needs to represent the state needed to process commands and not worry about the reads (like the Deactivate Inventory Item and associated comment example that Greg provides). And also commands that can be handled in a Transaction Script style manner by the command handler simply generating events and not touching the domain model. It also makes it easier for your senior developers to focus on the command behavior and ignore the queries, which is usually going to be a better use of their time. And of course scalability. If anybody out there has any thoughts on this and can help educate me further, please either leave a comment or feel free to get in touch with me via email:

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  • Performance considerations for common SQL queries

    - by Jim Giercyk
    Originally posted on: http://geekswithblogs.net/NibblesAndBits/archive/2013/10/16/performance-considerations-for-common-sql-queries.aspxSQL offers many different methods to produce the same results.  There is a never-ending debate between SQL developers as to the “best way” or the “most efficient way” to render a result set.  Sometimes these disputes even come to blows….well, I am a lover, not a fighter, so I decided to collect some data that will prove which way is the best and most efficient.  For the queries below, I downloaded the test database from SQLSkills:  http://www.sqlskills.com/sql-server-resources/sql-server-demos/.  There isn’t a lot of data, but enough to prove my point: dbo.member has 10,000 records, and dbo.payment has 15,554.  Our result set contains 6,706 records. The following queries produce an identical result set; the result set contains aggregate payment information for each member who has made more than 1 payment from the dbo.payment table and the first and last name of the member from the dbo.member table.   /*************/ /* Sub Query  */ /*************/ SELECT  a.[Member Number] ,         m.lastname ,         m.firstname ,         a.[Number Of Payments] ,         a.[Average Payment] ,         a.[Total Paid] FROM    ( SELECT    member_no 'Member Number' ,                     AVG(payment_amt) 'Average Payment' ,                     SUM(payment_amt) 'Total Paid' ,                     COUNT(Payment_No) 'Number Of Payments'           FROM      dbo.payment           GROUP BY  member_no           HAVING    COUNT(Payment_No) > 1         ) a         JOIN dbo.member m ON a.[Member Number] = m.member_no         /***************/ /* Cross Apply  */ /***************/ SELECT  ca.[Member Number] ,         m.lastname ,         m.firstname ,         ca.[Number Of Payments] ,         ca.[Average Payment] ,         ca.[Total Paid] FROM    dbo.member m         CROSS APPLY ( SELECT    member_no 'Member Number' ,                                 AVG(payment_amt) 'Average Payment' ,                                 SUM(payment_amt) 'Total Paid' ,                                 COUNT(Payment_No) 'Number Of Payments'                       FROM      dbo.payment                       WHERE     member_no = m.member_no                       GROUP BY  member_no                       HAVING    COUNT(Payment_No) > 1                     ) ca /********/                    /* CTEs  */ /********/ ; WITH    Payments           AS ( SELECT   member_no 'Member Number' ,                         AVG(payment_amt) 'Average Payment' ,                         SUM(payment_amt) 'Total Paid' ,                         COUNT(Payment_No) 'Number Of Payments'                FROM     dbo.payment                GROUP BY member_no                HAVING   COUNT(Payment_No) > 1              ),         MemberInfo           AS ( SELECT   p.[Member Number] ,                         m.lastname ,                         m.firstname ,                         p.[Number Of Payments] ,                         p.[Average Payment] ,                         p.[Total Paid]                FROM     dbo.member m                         JOIN Payments p ON m.member_no = p.[Member Number]              )     SELECT  *     FROM    MemberInfo /************************/ /* SELECT with Grouping   */ /************************/ SELECT  p.member_no 'Member Number' ,         m.lastname ,         m.firstname ,         COUNT(Payment_No) 'Number Of Payments' ,         AVG(payment_amt) 'Average Payment' ,         SUM(payment_amt) 'Total Paid' FROM    dbo.payment p         JOIN dbo.member m ON m.member_no = p.member_no GROUP BY p.member_no ,         m.lastname ,         m.firstname HAVING  COUNT(Payment_No) > 1   We can see what is going on in SQL’s brain by looking at the execution plan.  The Execution Plan will demonstrate which steps and in what order SQL executes those steps, and what percentage of batch time each query takes.  SO….if I execute all 4 of these queries in a single batch, I will get an idea of the relative time SQL takes to execute them, and how it renders the Execution Plan.  We can settle this once and for all.  Here is what SQL did with these queries:   Not only did the queries take the same amount of time to execute, SQL generated the same Execution Plan for each of them.  Everybody is right…..I guess we can all finally go to lunch together!  But wait a second, I may not be a fighter, but I AM an instigator.     Let’s see how a table variable stacks up.  Here is the code I executed: /********************/ /*  Table Variable  */ /********************/ DECLARE @AggregateTable TABLE     (       member_no INT ,       AveragePayment MONEY ,       TotalPaid MONEY ,       NumberOfPayments MONEY     ) INSERT  @AggregateTable         SELECT  member_no 'Member Number' ,                 AVG(payment_amt) 'Average Payment' ,                 SUM(payment_amt) 'Total Paid' ,                 COUNT(Payment_No) 'Number Of Payments'         FROM    dbo.payment         GROUP BY member_no         HAVING  COUNT(Payment_No) > 1   SELECT  at.member_no 'Member Number' ,         m.lastname ,         m.firstname ,         at.NumberOfPayments 'Number Of Payments' ,         at.AveragePayment 'Average Payment' ,         at.TotalPaid 'Total Paid' FROM    @AggregateTable at         JOIN dbo.member m ON m.member_no = at.member_no In the interest of keeping things in groupings of 4, I removed the last query from the previous batch and added the table variable query.  Here’s what I got:     Since we first insert into the table variable, then we read from it, the Execution Plan renders 2 steps.  BUT, the combination of the 2 steps is only 22% of the batch.  It is actually faster than the other methods even though it is treated as 2 separate queries in the Execution Plan.  The argument I often hear against Table Variables is that SQL only estimates 1 row for the table size in the Execution Plan.  While this is true, the estimate does not come in to play until you read from the table variable.  In this case, the table variable had 6,706 rows, but it still outperformed the other queries.  People argue that table variables should only be used for hash or lookup tables.  The fact is, you have control of what you put IN to the variable, so as long as you keep it within reason, these results suggest that a table variable is a viable alternative to sub-queries. If anyone does volume testing on this theory, I would be interested in the results.  My suspicion is that there is a breaking point where efficiency goes down the tubes immediately, and it would be interesting to see where the threshold is. Coding SQL is a matter of style.  If you’ve been around since they introduced DB2, you were probably taught a little differently than a recent computer science graduate.  If you have a company standard, I strongly recommend you follow it.    If you do not have a standard, generally speaking, there is no right or wrong answer when talking about the efficiency of these types of queries, and certainly no hard-and-fast rule.  Volume and infrastructure will dictate a lot when it comes to performance, so your results may vary in your environment.  Download the database and try it!

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  • Troubleshooting High-CPU Utilization for SQL Server

    - by Susantha Bathige
    The objective of this FAQ is to outline the basic steps in troubleshooting high CPU utilization on  a server hosting a SQL Server instance. The first and the most common step if you suspect high CPU utilization (or are alerted for it) is to login to the physical server and check the Windows Task Manager. The Performance tab will show the high utilization as shown below: Next, we need to determine which process is responsible for the high CPU consumption. The Processes tab of the Task Manager will show this information: Note that to see all processes you should select Show processes from all user. In this case, SQL Server (sqlserver.exe) is consuming 99% of the CPU (a normal benchmark for max CPU utilization is about 50-60%). Next we examine the scheduler data. Scheduler is a component of SQLOS which evenly distributes load amongst CPUs. The query below returns the important columns for CPU troubleshooting. Note – if your server is under severe stress and you are unable to login to SSMS, you can use another machine’s SSMS to login to the server through DAC – Dedicated Administrator Connection (see http://msdn.microsoft.com/en-us/library/ms189595.aspx for details on using DAC) SELECT scheduler_id ,cpu_id ,status ,runnable_tasks_count ,active_workers_count ,load_factor ,yield_count FROM sys.dm_os_schedulers WHERE scheduler_id See below for the BOL definitions for the above columns. scheduler_id – ID of the scheduler. All schedulers that are used to run regular queries have ID numbers less than 1048576. Those schedulers that have IDs greater than or equal to 1048576 are used internally by SQL Server, such as the dedicated administrator connection scheduler. cpu_id – ID of the CPU with which this scheduler is associated. status – Indicates the status of the scheduler. runnable_tasks_count – Number of workers, with tasks assigned to them that are waiting to be scheduled on the runnable queue. active_workers_count – Number of workers that are active. An active worker is never preemptive, must have an associated task, and is either running, runnable, or suspended. current_tasks_count - Number of current tasks that are associated with this scheduler. load_factor – Internal value that indicates the perceived load on this scheduler. yield_count – Internal value that is used to indicate progress on this scheduler.                                                                 Now to interpret the above data. There are four schedulers and each assigned to a different CPU. All the CPUs are ready to accept user queries as they all are ONLINE. There are 294 active tasks in the output as per the current_tasks_count column. This count indicates how many activities currently associated with the schedulers. When a  task is complete, this number is decremented. The 294 is quite a high figure and indicates all four schedulers are extremely busy. When a task is enqueued, the load_factor  value is incremented. This value is used to determine whether a new task should be put on this scheduler or another scheduler. The new task will be allocated to less loaded scheduler by SQLOS. The very high value of this column indicates all the schedulers have a high load. There are 268 runnable tasks which mean all these tasks are assigned a worker and waiting to be scheduled on the runnable queue.   The next step is  to identify which queries are demanding a lot of CPU time. The below query is useful for this purpose (note, in its current form,  it only shows the top 10 records). SELECT TOP 10 st.text  ,st.dbid  ,st.objectid  ,qs.total_worker_time  ,qs.last_worker_time  ,qp.query_plan FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) st CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle) qp ORDER BY qs.total_worker_time DESC This query as total_worker_time as the measure of CPU load and is in descending order of the  total_worker_time to show the most expensive queries and their plans at the top:      Note the BOL definitions for the important columns: total_worker_time - Total amount of CPU time, in microseconds, that was consumed by executions of this plan since it was compiled. last_worker_time - CPU time, in microseconds, that was consumed the last time the plan was executed.   I re-ran the same query again after few seconds and was returned the below output. After few seconds the SP dbo.TestProc1 is shown in fourth place and once again the last_worker_time is the highest. This means the procedure TestProc1 consumes a CPU time continuously each time it executes.      In this case, the primary cause for high CPU utilization was a stored procedure. You can view the execution plan by clicking on query_plan column to investigate why this is causing a high CPU load. I have used SQL Server 2008 (SP1) to test all the queries used in this article.

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  • Alert visualization recipe: Get out your blender, drop in some sp_send_dbmail, Google Charts API, add your favorite colors and sprinkle with html. Blend till it’s smooth and looks pretty enough to taste.

    - by Maria Zakourdaev
      I really like database monitoring. My email inbox have a constant flow of different types of alerts coming from our production servers with all kinds of information, sometimes more useful and sometimes less useful. Usually database alerts look really simple, it’s usually a plain text email saying “Prod1 Database data file on Server X is 80% used. You’d better grow it manually before some query triggers the AutoGrowth process”. Imagine you could have received email like the one below.  In addition to the alert description it could have also included the the database file growth chart over the past 6 months. Wouldn’t it give you much more information whether the data growth is natural or extreme? That’s truly what data visualization is for. Believe it or not, I have sent the graph below from SQL Server stored procedure without buying any additional data monitoring/visualization tool.   Would you like to visualize your database alerts like I do? Then like myself, you’d love the Google Charts. All you need to know is a little HTML and have a mail profile configured on your SQL Server instance regardless of the SQL Server version. First of all, I hope you know that the sp_send_dbmail procedure has a great parameter @body_format = ‘HTML’, which allows us to send rich and colorful messages instead of boring black and white ones. All that we need is to dynamically create HTML code. This is how, for instance, you can create a table and populate it with some data: DECLARE @html varchar(max) SET @html = '<html>' + '<H3><font id="Text" style='color: Green;'>Top Databases: </H3>' + '<table border="1" bordercolor="#3300FF" style='background-color:#DDF8CC' width='70%' cellpadding='3' cellspacing='3'>' + '<tr><font color="Green"><th>Database Name</th><th>Size</th><th>Physical Name</th></tr>' + CAST( (SELECT TOP 10                             td = name,'',                             td = size * 8/1024 ,'',                             td = physical_name              FROM sys.master_files               ORDER BY size DESC             FOR XML PATH ('tr'),TYPE ) AS VARCHAR(MAX)) + '</table>' EXEC msdb.dbo.sp_send_dbmail @recipients = '[email protected]', @subject ='Top databases', @body = @html, @body_format = 'HTML' This is the result:   If you want to add more visualization effects, you can use Google Charts Tools https://google-developers.appspot.com/chart/interactive/docs/index which is a free and rich library of data visualization charts, they’re also easy to populate and embed. There are two versions of the Google Charts Image based charts: https://google-developers.appspot.com/chart/image/docs/gallery/chart_gall This is an old version, it’s officially deprecated although it will be up for a next few years or so. I really enjoy using this one because it can be viewed within the email body. For mobile devices you need to change the “Load remote images” property in your email application configuration.           Charts based on JavaScript classes: https://google-developers.appspot.com/chart/interactive/docs/gallery This API is newer, with rich and highly interactive charts, and it’s much more easier to understand and configure. The only downside of it is that they cannot be viewed within the email body. Outlook, Gmail and many other email clients, as part of their security policy, do not run any JavaScript that’s placed within the email body. However, you can still enjoy this API by sending the report as an email attachment. Here is an example of the old version of Google Charts API, sending the same top databases report as in the previous example but instead of a simple table, this script is using a pie chart right from  the T-SQL code DECLARE @html  varchar(8000) DECLARE @Series  varchar(800),@Labels  varchar(8000),@Legend  varchar(8000);     SET @Series = ''; SET @Labels = ''; SET @Legend = ''; SELECT TOP 5 @Series = @Series + CAST(size * 8/1024 as varchar) + ',',                         @Labels = @Labels +CAST(size * 8/1024 as varchar) + 'MB'+'|',                         @Legend = @Legend + name + '|' FROM sys.master_files ORDER BY size DESC SELECT @Series = SUBSTRING(@Series,1,LEN(@Series)-1),         @Labels = SUBSTRING(@Labels,1,LEN(@Labels)-1),         @Legend = SUBSTRING(@Legend,1,LEN(@Legend)-1) SET @html =   '<H3><font color="Green"> '+@@ServerName+' top 5 databases : </H3>'+    '<br>'+    '<img src="http://chart.apis.google.com/chart?'+    'chf=bg,s,DDF8CC&'+    'cht=p&'+    'chs=400x200&'+    'chco=3072F3|7777CC|FF9900|FF0000|4A8C26&'+    'chd=t:'+@Series+'&'+    'chl='+@Labels+'&'+    'chma=0,0,0,0&'+    'chdl='+@Legend+'&'+    'chdlp=b"'+    'alt="'+@@ServerName+' top 5 databases" />'              EXEC msdb.dbo.sp_send_dbmail @recipients = '[email protected]',                             @subject = 'Top databases',                             @body = @html,                             @body_format = 'HTML' This is what you get. Isn’t it great? Chart parameters reference: chf     Gradient fill  bg - backgroud ; s- solid cht     chart type  ( p - pie) chs        chart size width/height chco    series colors chd        chart data string        1,2,3,2 chl        pir chart labels        a|b|c|d chma    chart margins chdl    chart legend            a|b|c|d chdlp    chart legend text        b - bottom of chart   Line graph implementation is also really easy and powerful DECLARE @html varchar(max) DECLARE @Series varchar(max) DECLARE @HourList varchar(max) SET @Series = ''; SET @HourList = ''; SELECT @HourList = @HourList + SUBSTRING(CONVERT(varchar(13),last_execution_time,121), 12,2)  + '|' ,              @Series = @Series + CAST( COUNT(1) as varchar) + ',' FROM sys.dm_exec_query_stats s     CROSS APPLY sys.dm_exec_sql_text(plan_handle) t WHERE last_execution_time > = getdate()-1 GROUP BY CONVERT(varchar(13),last_execution_time,121) ORDER BY CONVERT(varchar(13),last_execution_time,121) SET @Series = SUBSTRING(@Series,1,LEN(@Series)-1) SET @html = '<img src="http://chart.apis.google.com/chart?'+ 'chco=CA3D05,87CEEB&'+ 'chd=t:'+@Series+'&'+ 'chds=1,350&'+ 'chdl= Proc executions from cache&'+ 'chf=bg,s,1F1D1D|c,lg,0,363433,1.0,2E2B2A,0.0&'+ 'chg=25.0,25.0,3,2&'+ 'chls=3|3&'+ 'chm=d,CA3D05,0,-1,12,0|d,FFFFFF,0,-1,8,0|d,87CEEB,1,-1,12,0|d,FFFFFF,1,-1,8,0&'+ 'chs=600x450&'+ 'cht=lc&'+ 'chts=FFFFFF,14&'+ 'chtt=Executions for from' +(SELECT CONVERT(varchar(16),min(last_execution_time),121)          FROM sys.dm_exec_query_stats          WHERE last_execution_time > = getdate()-1) +' till '+ +(SELECT CONVERT(varchar(16),max(last_execution_time),121)     FROM sys.dm_exec_query_stats) + '&'+ 'chxp=1,50.0|4,50.0&'+ 'chxs=0,FFFFFF,12,0|1,FFFFFF,12,0|2,FFFFFF,12,0|3,FFFFFF,12,0|4,FFFFFF,14,0&'+ 'chxt=y,y,x,x,x&'+ 'chxl=0:|1|350|1:|N|2:|'+@HourList+'3:|Hour&'+ 'chma=55,120,0,0" alt="" />' EXEC msdb.dbo.sp_send_dbmail @recipients = '[email protected]', @subject ='Daily number of executions', @body = @html, @body_format = 'HTML' Chart parameters reference: chco    series colors chd        series data chds    scale format chdl    chart legend chf        background fills chg        grid line chls    line style chm        line fill chs        chart size cht        chart type chts    chart style chtt    chart title chxp    axis label positions chxs    axis label styles chxt    axis tick mark styles chxl    axis labels chma    chart margins If you don’t mind to get your charts as an email attachment, you can enjoy the Java based Google Charts which are even easier to configure, and have much more advanced graphics. In the example below, the sp_send_email procedure uses the parameter @query which will be executed at the time that sp_send_dbemail is executed and the HTML result of this execution will be attached to the email. DECLARE @html varchar(max),@query varchar(max) DECLARE @SeriesDBusers  varchar(800);     SET @SeriesDBusers = ''; SELECT @SeriesDBusers = @SeriesDBusers +  ' ["'+DB_NAME(r.database_id) +'", ' +cast(count(1) as varchar)+'],' FROM sys.dm_exec_requests r GROUP BY DB_NAME(database_id) ORDER BY count(1) desc; SET @SeriesDBusers = SUBSTRING(@SeriesDBusers,1,LEN(@SeriesDBusers)-1) SET @query = ' PRINT '' <html>   <head>     <script type="text/javascript" src="https://www.google.com/jsapi"></script>     <script type="text/javascript">       google.load("visualization", "1", {packages:["corechart"]});        google.setOnLoadCallback(drawChart);       function drawChart() {                      var data = google.visualization.arrayToDataTable([                        ["Database Name", "Active users"],                        '+@SeriesDBusers+'                      ]);                        var options = {                        title: "Active users",                        pieSliceText: "value"                      };                        var chart = new google.visualization.PieChart(document.getElementById("chart_div"));                      chart.draw(data, options);       };     </script>   </head>   <body>     <table>     <tr><td>         <div id="chart_div" style='width: 800px; height: 300px;'></div>         </td></tr>     </table>   </body> </html> ''' EXEC msdb.dbo.sp_send_dbmail    @recipients = '[email protected]',    @subject ='Active users',    @body = @html,    @body_format = 'HTML',    @query = @Query,     @attach_query_result_as_file = 1,     @query_attachment_filename = 'Results.htm' After opening the email attachment in the browser you are getting this kind of report: In fact, the above is not only for database alerts. It can be used for applicative reports if you need high levels of customization that you cannot achieve using standard methods like SSRS. If you need more information on how to customize the charts, you can try the following: Image Based Charts wizard https://google-developers.appspot.com/chart/image/docs/chart_wizard  Live Image Charts Playground https://google-developers.appspot.com/chart/image/docs/chart_playground Image Based Charts Parameters List https://google-developers.appspot.com/chart/image/docs/chart_params Java Script Charts Playground https://code.google.com/apis/ajax/playground/?type=visualization Use the above examples as a starting point for your procedures and I’d be more than happy to hear of your implementations of the above techniques. Yours, Maria

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  • LINQ to XML

    Gain an understanding of LINQ (Language Integrated Query) to XML and see why you'll never want to use the DOM again.

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  • Google Webmasters tools search queries position

    - by user1592845
    In my website account on Google Webmasters tools, some search queries show average position 1.0. This make me understand that it should be displayed as the first result. When I search for this query I could not able to find my website's page listed as a result?! In some cases I navigate to the third or the fourth result page and I could not find it! What are factors that make my website loss its average position for a search query? and when Google webmasters tools updates their values?

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  • Partition Wise Joins II

    - by jean-pierre.dijcks
    One of the things that I did not talk about in the initial partition wise join post was the effect it has on resource allocation on the database server. When Oracle applies a different join method - e.g. not PWJ - what you will see in SQL Monitor (in Enterprise Manager) or in an Explain Plan is a set of producers and a set of consumers. The producers scan the tables in the the join. If there are two tables the producers first scan one table, then the other. The producers thus provide data to the consumers, and when the consumers have the data from both scans they do the join and give the data to the query coordinator. Now that behavior means that if you choose a degree of parallelism of 4 to run such query with, Oracle will allocate 8 parallel processes. Of these 8 processes 4 are producers and 4 are consumers. The consumers only actually do work once the producers are fully done with scanning both sides of the join. In the plan above you can see that the producers access table SALES [line 11] and then do a PX SEND [line 9]. That is the producer set of processes working. The consumers receive that data [line 8] and twiddle their thumbs while the producers go on and scan CUSTOMERS. The producers send that data to the consumer indicated by PX SEND [line 5]. After receiving that data [line 4] the consumers do the actual join [line 3] and give the data to the QC [line 2]. BTW, the myth that you see twice the number of processes due to the setting PARALLEL_THREADS_PER_CPU=2 is obviously not true. The above is why you will see 2 times the processes of the DOP. In a PWJ plan the consumers are not present. Instead of producing rows and giving those to different processes, a PWJ only uses a single set of processes. Each process reads its piece of the join across the two tables and performs the join. The plan here is notably different from the initial plan. First of all the hash join is done right on top of both table scans [line 8]. This query is a little more complex than the previous so there is a bit of noise above that bit of info, but for this post, lets ignore that (sort stuff). The important piece here is that the PWJ plan typically will be faster and from a PX process number / resources typically cheaper. You may want to look out for those plans and try to get those to appear a lot... CREDITS: credits for the plans and some of the info on the plans go to Maria, as she actually produced these plans and is the expert on plans in general... You can see her talk about explaining the explain plan and other optimizer stuff over here: ODTUG in Washington DC, June 27 - July 1 On the Optimizer blog At OpenWorld in San Francisco, September 19 - 23 Happy joining and hope to see you all at ODTUG and OOW...

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  • DBCC MEMUSAGE in 2005/8 ?

    - by steveh99999
    I used to like using undocumented command DBCC MEMUSAGE in SQL 2000 to see which tables were using space in SQL data cache. In SQL 2005, this command is not longer present. Instead a DMV – sys.dm_os_buffer_descriptors – can be used to display data cache contents,  but this doesn’t quite give you the same output as DBCC MEMUSAGE. I’m also aware that you can use Quest’s spotlight tool to view a summary of data cache contents. Using  this post by Umachandar Jayachandran  of Microsoft, I was able to create the following equivalent for SQL 2005/8. I’ve wrapped Umachandar’s original query in a CTE to produce summary information :- ;WITH memusage_CTE AS (SELECT bd.database_id, bd.file_id, bd.page_id, bd.page_type , COALESCE(p1.object_id, p2.object_id) AS object_id , COALESCE(p1.index_id, p2.index_id) AS index_id , bd.row_count, bd.free_space_in_bytes, CONVERT(TINYINT,bd.is_modified) AS 'DirtyPage' FROM sys.dm_os_buffer_descriptors AS bd JOIN sys.allocation_units AS au ON au.allocation_unit_id = bd.allocation_unit_id OUTER APPLY ( SELECT TOP(1) p.object_id, p.index_id FROM sys.partitions AS p WHERE p.hobt_id = au.container_id AND au.type IN (1, 3) ) AS p1 OUTER APPLY ( SELECT TOP(1) p.object_id, p.index_id FROM sys.partitions AS p WHERE p.partition_id = au.container_id AND au.type = 2 ) AS p2 WHERE  bd.database_id = DB_ID() AND bd.page_type IN ('DATA_PAGE', 'INDEX_PAGE') ) SELECT TOP 20 DB_NAME(database_id) AS 'Database',OBJECT_NAME(object_id,database_id) AS 'Table Name', index_id,COUNT(*) AS 'Pages in Cache', SUM(dirtyPage) AS 'Dirty Pages' FROM memusage_CTE GROUP BY database_id, object_id, index_id ORDER BY COUNT(*) DESC I’m not 100% happy with the results of the above query however… I’ve noticed that on a busy BizTalk messageBox database  it will return information on pages that contain GHOST rows – . ie where data has already been deleted but has yet to be cleaned-up by a background process – I’m need to investigate further why cache on this server apparently contains so much GHOST data… For more information on the background ghost cleanup process, see this article by Paul Randall. However, I think the results of this query should still be of interest to a DBA. I have another post to come shortly regarding an example I encountered where this information proved useful to me… I notice in SQL 2008, sys.dm_os_buffer_descriptors gained an extra column – numa_mode – I’m interested to see how this is populated and how useful this column can be on a NUMA-enabled system. I’m assuming in theory you could use this column to help analyse how your tables are spread across Numa-enabled data-cache ?

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  • SPARC M7 Chip - 32 cores - Mind Blowing performance

    - by Angelo-Oracle
    The M7 Chip Oracle just announced its Next Generation Processor at the HotChips HC26 conference. As the Tech Lead in our Systems Division's Partner group, I had a front row seat to the extraordinary price performance advantage of Oracle current T5 and M6 based systems. Partner after partner tested  these systems and were impressed with it performance. Just read some of the quotes to see what our partner has been saying about our hardware. We just announced our next generation processor, the M7. This has 32 cores (up from 16-cores in T5 and 12-cores in M6). With 20 nm technology  this is our most advanced processor. The processor has more cores than anything else in the industry today. After the Sun acquisition Oracle has released 5 processors in 4 years and this is the 6th.  The S4 core  The M7 is built using the foundation of the S4 core. This is the next generation core technology. Like its predecessor, the S4 has 8 dynamic threads. It increases the frequency while maintaining the Pipeline depth. Each core has its own fine grain power estimator that keeps the core within its power envelop in 250 nano-sec granularity. Each core also includes Software in Silicon features for Application Acceleration Support. Each core includes features to improve Application Data Integrity, with almost no performance loss. The core also allows using part of the Virtual Address to store meta-data.  User-Level Synchronization Instructions are also part of the S4 core. Each core has 16 KB Instruction and 16 KB Data L1 cache. The Core Clusters  The cores on the M7 chip are organized in sets of 4-core clusters. The core clusters share  L2 cache.  All four cores in the complex share 256 KB of 4 way set associative L2 Instruction Cache, with over 1/2 TB/s of throughput. Two cores share 256 KB of 8 way set associative L2 Data Cache, with over 1/2 TB/s of throughput. With this innovative Core Cluster architecture, the M7 doubles core execution bandwidth. to maximize per-thread performance.  The Chip  Each  M7 chip has 8 sets of these core-clusters. The chip has 64 MB on-chip L3 cache. This L3 caches is shared among all the cores and is partitioned into 8 x 8 MB chunks. Each chunk is  8-way set associative cache. The aggregate bandwidth for the L3 cache on the chip is over 1.6TB/s. Each chip has 4 DDR4 memory controllers and can support upto 16 DDR4 DIMMs, allowing for 2 TB of RAM/chip. The chip also includes 4 internal links of PCIe Gen3 I/O controllers.  Each chip has 7 coherence links, allowing for 8 of these chips to be connected together gluelessly. Also 32 of these chips can be connected in an SMP configuration. A potential system with 32 chips will have 1024 cores and 8192 threads and 64 TB of RAM.  Software in Silicon The M7 chip has many built in Application Accelerators in Silicon. These features will be exposed to our Software partners using the SPARC Accelerator Program.  The M7  has built-in logic to decompress data at the speed of memory access. This means that applications can directly work on compressed data in memory increasing the data access rates. The VA Masking feature allows the use of part of the virtual address to store meta-data.  Realtime Application Data Integrity The Realtime Application Data Integrity feature helps applications safeguard against invalid, stale memory reference and buffer overflows. The first 4-bits if the Pointer can be used to store a version number and this version number is also maintained in the memory & cache lines. When a pointer accesses memory the hardware checks to make sure the two versions match. A SEGV signal is raised when there is a mismatch. This feature can be used by the Database, applications and the OS.  M7 Database In-Memory Query Accelerator The M7 chip also includes a In-Silicon Query Engines.  These accelerate tasks that work on In-Memory Columnar Vectors. Oracle In-Memory options stores data in Column Format. The M7 Query Engine can speed up In-Memory Format Conversion, Value and Range Comparisons and Set Membership lookups. This engine can work on Compressed data - this means not only are we accelerating the query performance but also increasing the memory bandwidth for queries.  SPARC Accelerated Program  At the Hotchips conference we also introduced the SPARC Accelerated Program to provide our partners and third part developers access to all the goodness of the M7's SPARC Application Acceleration features. Please get in touch with us if you are interested in knowing more about this program. 

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