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  • Would you allow this type of query?

    - by user564577
    I'm exploring using an ORM tool in our development shop, and in particular Entity Framework 4.0. Since we work with VERY large databases, I'm a bit concerned about the query's it generates. Doing something simple like getting clients with an address in a state looks like below. As a database developer or admin would you allow this? Is it as bad as it looks? Assume every join is on a clustered index. SELECT [Project2].[ClientKey] AS [ClientKey], [Project2].[FirstName] AS [FirstName], [Project2].[LastName] AS [LastName], [Project2].[IsEnabled] AS [IsEnabled], [Project2].[ChangeUser] AS [ChangeUser], [Project2].[ChangeDate] AS [ChangeDate], [Project2].[C1] AS [C1], [Project2].[AddressKey] AS [AddressKey], [Project2].[ClientKey1] AS [ClientKey1], [Project2].[AddressTypeCode] AS [AddressTypeCode], [Project2].[PrimaryAddress] AS [PrimaryAddress], [Project2].[AddressLine1] AS [AddressLine1], [Project2].[AddressLine2] AS [AddressLine2], [Project2].[City] AS [City], [Project2].[State] AS [State], [Project2].[ZIP] AS [ZIP] FROM ( SELECT [Distinct1].[ClientKey] AS [ClientKey], [Distinct1].[FirstName] AS [FirstName], [Distinct1].[LastName] AS [LastName], [Distinct1].[IsEnabled] AS [IsEnabled], [Distinct1].[ChangeUser] AS [ChangeUser], [Distinct1].[ChangeDate] AS [ChangeDate], [Extent3].[AddressKey] AS [AddressKey], [Extent3].[ClientKey] AS [ClientKey1], [Extent3].[AddressTypeCode] AS [AddressTypeCode], [Extent3].[PrimaryAddress] AS [PrimaryAddress], [Extent3].[AddressLine1] AS [AddressLine1], [Extent3].[AddressLine2] AS [AddressLine2], [Extent3].[City] AS [City], [Extent3].[State] AS [State], [Extent3].[ZIP] AS [ZIP], CASE WHEN ([Extent3].[AddressKey] IS NULL) THEN CAST(NULL AS int) ELSE 1 END AS [C1] FROM (SELECT DISTINCT [Extent1].[ClientKey] AS [ClientKey], [Extent1].[FirstName] AS [FirstName], [Extent1].[LastName] AS [LastName], [Extent1].[IsEnabled] AS [IsEnabled], [Extent1].[ChangeUser] AS [ChangeUser], [Extent1].[ChangeDate] AS [ChangeDate] FROM [Common].[Clients] AS [Extent1] INNER JOIN [Common].[ClientAddresses] AS [Extent2] ON [Extent1].[ClientKey] = [Extent2].[ClientKey] WHERE (( CAST(CHARINDEX(UPPER('D'), UPPER([Extent1].[LastName])) AS int)) > 0) AND ([Extent1].[IsEnabled] = 1) AND ([Extent2].[City] IS NOT NULL) AND ((UPPER([Extent2].[City])) = (UPPER('Colorado Springs'))) ) AS [Distinct1] LEFT OUTER JOIN [Common].[ClientAddresses] AS [Extent3] ON [Distinct1].[ClientKey] = [Extent3].[ClientKey] ) AS [Project2] ORDER BY [Project2].[ClientKey] ASC, [Project2].[FirstName] ASC, [Project2].[LastName] ASC, [Project2].[IsEnabled] ASC, [Project2].[ChangeUser] ASC, [Project2].[ChangeDate] ASC, [Project2].[C1] ASC

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  • How do I put data from multiple records into different columns?

    - by Bryan
    My two tables are titled analyzed and analyzedCopy3. I'm trying to put information from analyzedCopy3 into multiple columns in analyzed. Sample data from analyzedCopy3: readings_miu_id OriginalCol ColRSSIz 110001366 Frederick Road -108 110001366 Steel Street 110001366 Fifth Ave. 110001508 Steel Street -104 What I want to do is put the top 3 OriginalCol, ColRSSIz combinations into columns that I have in the table analyzed. In analyzed there is only one record for each unique readings_miu_id. Any ideas? Thanks in advance. Additional Info: By "top 3 OriginalCol, ColRSSIz combinations" I mean the first 3 combinations with the highest value in the ColRSSIz column. For any readings_miu_id there could be anywhere from 1 row of information to 6 rows of information. So at most I'm only wanting the top 3. If there is less than 3 rows for the readings_miu_id then the other columns need to be blank. Query that generates the table "analyzed": strSql4 = " SELECT readings_miu_id, Count(readings_miu_id) as NumberOfReads, First(PercentSuccessz) as PercentSuccess, First(Readingz)as Reading, First(MIUwindowz) as MIUwindow, First(SNz) as SN, First(Noisez) as Noise, First(RSSIz) as RSSI, First(ColRSSIz) as ColRSSI, First(MIURSSIz) as MIURSSI, First(Col1z) as Col1, First(Col1RSSIz) as Col1RSSI, First(Col2z) as Col2, First(Col2RSSIz) as Col2RSSI, First(Col3z) as Col3, First(Col3RSSIz) as Col3RSSI, First(Firmwarez) as Firmware, First(CFGDatez) as CFGDate, First(FreqCorrz) as FreqCorr, First(Activez) as Active, First(MeterTypez) as MeterType, First(OriginColz) as OriginCol, First(ColIDz) as ColID, First(Ownagez) as Ownage, First(SiteIDz) as SiteID, First(PremIDz) as PremID, First(prem_group1z) as prem_group1, First(prem_group2z) as prem_group2, First(ReadIDz) as ReadID, First(prem_addr1z) as prem_addr1 " & _ "INTO analyzed " & _ "FROM analyzedCopy2 " & _ "GROUP BY readings_miu_id, PremIDz; " DoCmd.SetWarnings False DoCmd.RunSQL strSql4 DoCmd.SetWarnings True

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  • How to combine two rows and calculate the time difference between two timestamp values in MySQL?

    - by Nadar
    I have a situation that I'm sure is quite common and it's really bothering me that I can't figure out how to do it or what to search for to find a relevant example/solution. I'm relatively new to MySQL (have been using MSSQL and PostgreSQL earlier) and every approach I can think of is blocked by some feature lacking in MySQL. I have a "log" table that simply lists many different events with their timestamp (stored as datetime type). There's lots of data and columns in the table not relevant to this problem, so lets say we have a simple table like this: CREATE TABLE log ( id INT NOT NULL AUTO_INCREMENT, name VARCHAR(16), ts DATETIME NOT NULL, eventtype VARCHAR(25), PRIMARY KEY (id) ) Let's say that some rows have an eventtype = 'start' and others have an eventtype = 'stop'. What I want to do is to somehow couple each "startrow" with each "stoprow" and find the time difference between the two (and then sum the durations per each name, but that's not where the problem lies). Each "start" event should have a corresponding "stop" event occuring at some stage later then the "start" event, but because of problems/bugs/crashed with the data collector it could be that some are missing. In that case I would like to disregard the event without a "partner". That means that given the data: foo, 2010-06-10 19:45, start foo, 2010-06-10 19:47, start foo, 2010-06-10 20:13, stop ..I would like to just disregard the 19:45 start event and not just get two result rows both using the 20:13 stop event as the stop time. I've tried to join the table with itself in different ways, but the key problems for me seems to be to find a way to correctly identify the corresponding "stop" event to the "start" event for the given "name". The problem is exactly the same as you would have if you had table with employees stamping in and out of work and wanted to find out how much they actually were at work. I'm sure there must be well known solutions to this, but I can't seem to find them...

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  • What is the most "database independent" way of creating a variable length text field in a database

    - by Thibaut Colar
    I want to create a text field in the database, with no specific size (it will store text of length unknown in some case) - the particular text are serialized simple object (~ JSON) What is the most database independent way to do this : - a varchar with no size specified (don't think all db support this) - a 'text' field, this seems to be common, but I don't believe it's a standard - a blob or other object of that kind ? - a varchar of a a very large size (that's inefficient and wastes disk space probably) - Other ? I'm using JDBC, but I'd like to use something that is supported in most DB (oracle, mysql, postgresql, derby, HSQL, H2 etc...) Thanks.

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  • What is the current status on Microsoft ProClarity?

    - by Ali_Abadani
    I don't really know how to compose this question. My complay has been using Microsoft ProClarity for few years and we have a quite a few users using it publising books and doing ad-hoc analysis. With the new Microsoft BI solutions, it seems like they are completely going away from ProClarity and replacing the OLAP analysis with Excel. I understand the with SharePoint and integration with PerformancePoint and reporting services the dashboards and reports would be done in SharePoint but what about the analysis? Any ideas?

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  • user_objects oracle

    - by mysticfalls
    I would just like to ask what is the difference between user_constraints and user_objects. I have this two database. I run a script on both DB that resulted a unique constraint error. To solve the problem I delete the constraint on user_constraint table for both DB. After that DB1 run without error.. DB2 however failed, I checked the user_constraint for both db and the constraints was deleted. I was asked to check the user_objects.. and found that DB2 has that same constraint_name as the object_name in user_objects table.. Any info regarding their relationship, use, similarites, etc will be appreciated ... Thanks..

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  • Question on different ways to link tables

    - by dotnetdev
    What is the difference between linking two tables and then the PK is an FK in the other table, but the FK has not got the primary key option (so it does not have the gold key), and having the PK in one table as a PK in another table? Am I right to think that the second option is for a many-to-many relationship? Thanks

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  • Conditional sorting in MySQL?

    - by serg555
    I have "tasks" table with 3 fields: date priority (0,1,2) done (0,1) What I am trying to achieve is with the whole table sorted by done flag, tasks that are not done should be sorted by priority, while tasks that are done should be sorted by date: Select * from tasks order by done asc If done=0 additionally order by priority desc If done=1 additionally order by date desc Is it possible to do this in MySQL without unions? Thanks.

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  • How do I do a table join on two fields in my second table?

    - by Cannonade
    I have two tables: Messages - Amongst other things, has a to_id and a from_id field. People - Has a corresponding person_id I am trying to figure out how to do the following in a single linq query: Give me all messages that have been sent to and from person x (idself). I had a couple of cracks at this. Not quite right MsgPeople = (from p in db.people join m in db.messages on p.person_id equals m.from_id where (m.from_id == idself || m.to_id == idself) orderby p.name descending select p).Distinct(); This almost works, except I think it misses one case: "people who have never received a message, just sent one to me" How this works in my head So what I really need is something like: join m in db.messages on (p.people_id equals m.from_id or p.people_id equals m.to_id) Gets me a subset of the people I am after It seems you can't do that. I have tried a few other options, like doing two joins: MsgPeople = (from p in db.people join m in AllMessages on p.person_id equals m.from_id join m2 in AllMessages on p.person_id equals m2.to_id where (m2.from_id == idself || m.to_id == idself) orderby p.name descending select p).Distinct(); but this gives me a subset of the results I need, I guess something to do with the order the joins are resolved. My understanding of LINQ (and perhaps even database theory) is embarrassingly superficial and I look forward to having some light shed on my problem.

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  • How to renumber primary index.

    - by Kamil Mroczek
    I have got a simple MySQL table and primary index (id) is not numbered one by one (1, 31, 35, 100 etc.). I want them to be numbered like (1, 2, 3, 4). Please tell me how to do it. I would also like to point that I am aware of possible consequences of the operation, but I just want to tidy up the table.

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  • select row from table and substitute a field with one from another column if it exists

    - by EarthMind
    I'm trying construct a PostgreSQL query that does the following but so far my efforts have been in vain. Problem: There are two tables: A and B. I'd like to select all columns from table A (having columns: id, name, description) and substitute the "A.name" column with the value of the column "B.title" from table B (having columns: id, table_A_id title, langcode) where B.table_A_id is 5 and B.langcode is "nl" (if there are any rows). My attempts: SELECT A.name, case when exists(select title from B where table_A_id = 5 and langcode= 'nl') then B.title else A.name END FROM A, B WHERE A.id = 5 and B.table_A_id = 5 and B.langcode = 'nl' -- second try: SELECT COALESCE(B.title, A.name) as name from A, B where A.id = 5 and B.table_A_id = 5 and exists(select title from B where table_A_id = 5 and langcode= 'nl') I've tried using a CASE and COALESCE() but failed due to my inexperience with both concepts. Thanks in advance.

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  • Can I lock rows in a cursor if the cursor only returns a single count(*) row?

    - by RenderIn
    I would like to restrict users from inserting more than 3 records with color = 'Red' in my FOO table. My intentions are to A) retrieve the current count so that I can determine whether another record is allowed and B) prevent any other processes from inserting any Red records while this one is in process, hence the for update of. I'd like to do something like: cursor cur_cnt is select count(*) cnt from foo where foo.color = 'Red' for update of foo.id; Will this satisfy both my requirements or will it not lock only the rows in the count(*) who had foo.color = 'Red'?

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  • SqlCeCommand ExecuteNonQuery performance issue

    - by Michael
    I've been asked to resolve an issue with a .Net/SqlServerCe application. Specifically, after repeated inserts against the db, performance becomes increasingly degraded. In one instance at ~200 rows, in another at ~1000 rows. In the latter case the code being used looks like this: Dim cm1 As System.Data.SqlServerCe.SqlCeCommand = cn1.CreateCommand cm1.CommandText = "INSERT INTO Table1 Values(?,?,?,?,?,?,?,?,?,?,?,?,?)" For j = 0 To ds.Tables(0).Rows.Count - 1 'this is 3110 For i = 0 To 12 cm1.Parameters(tbl(i, 0)).Value = Vals(j,i) 'values taken from a different db Next cm1.ExecuteNonQuery() Next The specifics aren't super important (like what 'tbl' is, etc) but rather whether or not this code should be expected to handle this number of inserts, or if the crawl I'm witnessing is to be expected.

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  • Some help needed with a SQL query

    - by Psyche
    Hello, I need some help with a MySQL query. I have two tables, one with offers and one with statuses. An offer can has one or more statuses. What I would like to do is get all the offers and their latest status. For each status there's a table field named 'added' which can be used for sorting. I know this can be easily done with two queries, but I need to make it with only one because I also have to apply some filters later in the project. Here's my setup: CREATE TABLE `test`.`offers` ( `id` INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY , `client` TEXT NOT NULL , `products` TEXT NOT NULL , `contact` TEXT NOT NULL ) ENGINE = MYISAM ; CREATE TABLE `statuses` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `offer_id` int(11) NOT NULL, `options` text NOT NULL, `deadline` date NOT NULL, `added` datetime NOT NULL, PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1

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  • Comma separated values in a database field

    - by John Doe
    I have a products table. Each row in that table corresponds to a single product and it's identified by a unique Id. Now each product can have multiple "codes" associated with that product. For example: Id | Code ---------------------- 0001 | IN,ON,ME,OH 0002 | ON,VI,AC,ZO 0003 | QA,PS,OO,ME What I'm trying to do is create a stored procedure so that I can pass in a codes like "ON,ME" and have it return every product that contains the "ON" or "ME" code. Since the codes are comma separated, I don't know how I can split those and search them. Is this possible using only TSQL? Edit: It's a mission critical table. I don't have the authority to change it.

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  • Multiple LIKE, OR MySql Queries Match

    - by Codex73
    Search for: 'chemist' Problem: query which will match a string like 'onechemist' but not 'chemist'. SELECT id,name FROM `records` WHERE name LIKE '%". mysql_real_escape_string($q) ."%' This alternate try won't work: SELECT id,name FROM `records` WHERE name LIKE '%". mysql_real_escape_string($q) ."%' OR name LIKE '". mysql_real_escape_string($q) ."%' OR name LIKE '%". mysql_real_escape_string($q) ."' How could I compile the above into one single query that will match any field which has the string or optimize the query into a better expression?

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  • Is SQLlite strong enough to use as wordpress database ?

    - by justjoe
    i'm just curious. so i ask this particular question about SQLite. I haven't use this type of database extensively. but care to explain what is the basic different between SQLite and Mysql ? The reason behind all of this is i just want to know whether it possible to use it to store wordpress data and act as a database ?

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  • Wanted: Good examples of Scala database persistence

    - by Rydell
    I'm would like to use Scala to persist data to a relational database, so what I am looking for are examples of CRUD operations using Scala. I would like to code on a lower level of abstraction than an ORM like Hibernate/Toplink (read:JDBC), but between us, I would like to see examples of all types. Thanks folks.

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  • access: control source of textbox

    - by I__
    there is a form where a user enters a date in [Text4] when users clicks OK, the following code is run: DoCmd.OpenReport "All_Ones", acViewPreview the following is the control source of a textbox on the report [Forms]![By Number]![Text4] for some reason after the report is open, it just sayd #?nameor something like that, meaning that it is an invalid parameter. what am i doing wrong?

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  • select row from table and substitute a field with one from another column if not null

    - by EarthMind
    I'm trying construct a PostgreSQL query that does the following but so far my efforts have been in vain. Problem: There are two tables: A and B. I'd like to select all columns from table A (having columns: id, name, description) and substitute the "A.name" column with the value of the column "B.title" from table B (having columns: id, table_A_id title, langcode) where B.table_A_id is 5 and B.langcode is "nl" (if there are any rows). I've tried using a CASE and COALESCE() but failed due to my inexperience with both concepts. Thanks in advance.

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  • Any way to make this PostgreSQL count query any faster?

    - by Ben Dauphinee
    I'm running a case-insensitive search on a table with 7.2 million rows, and I was wondering if there was any way to make this query any faster? Currently, it takes approx 11.6 seconds to execute, with just one search parameter, and I'm worried that as soon as I add more than one, this query will become massively slow. SELECT count(*) FROM "exif_parse" WHERE (description ~* 'canon')

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  • MySQL COUNT() total posts within a specific criteria?

    - by newbtophp
    Hey, I've been losing my hair trying to figure out what I'm doing wrong, let me explain abit about my MySQL structure (so you get a better understanding) before I go straight to the question. I have a simple PHP forum and I have a column in both tables (for posts and topics) named 'deleted' if it equals 0 that means its displayed (considered not deleted/exists) or if it equals 1 it hidden (considered deleted/doesn't exist) - bool/lean. Now, the 'specific criteria' I'm on about...I'm wanting to get a total post count within a specific forum using its id (forum_id), ensuring it only counts posts which are not deleted (deleted = 0) and their parent topics are not deleted either (deleted = 0). The column/table names are self explanatory (see my efforts below for them - if needed). I've tried the following (using a 'simple' JOIN): SELECT COUNT(t1.post_id) FROM forum_posts AS t1, forum_topics AS t2 WHERE t1.forum_id = '{$forum_id}' AND t1.deleted = 0 AND t1.topic_id = t2.topic_id AND t2.deleted = 0 LIMIT 1 I've also tried this (using a Subquery): SELECT COUNT(t1.post_id) FROM forum_posts AS t1 WHERE t1.forum_id = '{$forum_id}' AND t1.deleted = 0 AND (SELECT deleted FROM forum_topics WHERE topic_id = t1.topic_id) = 0 LIMIT 1 But both don't comply with the specific criteria. Appreciate all help! :)

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