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• New technical whitepaper on Database-as-a-Service

  - by Javier Puerta

  High Availability Best Practices for Database Consolidation- The Foundation for Database-as-a-Service. An Oracle White Paper - April 2014 This paper provides MAA best practices for Database Consolidation using Oracle Multitenant. It describes standard HA architectures that are the foundation for DBaaS. It is most appropriate for a technical audience: Architects, Directors of IT and Database Administrators responsible for the consolidation and migration of traditional database deployments to DBaaS.  Recommended best practices are equally relevant to any platform supported by Oracle Database except where explicitly noted as being an optimization or an example that applies only to Oracle Engineered systems. 

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• Which database to use for quickly and pygtk

  - by usher

  I'm writing application using quickly Pygtk and glade. this application should have database connection (such as MySQL) for reading and writing data from the local or outsourcing machine \ server. However, in my machine there is MySQL installed, but when releasing the app it sould be installed on another ubuntu machine, which may not have mysql and moreover not the same database with the required database name and structure.... So my questions are: Is it a good choice using mysql as database 1.2 If not what is? Is it posible to embeding mysql or other database program during the installation from ubuntu software center? 2.2 If it's posible: hwo(any tutorial?) Where to store secure data outside the mysql (or whatever) for conecting the database every time a user launch the application

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• What are some ways people deploy relational database changes using Node.js? [closed]

  - by JamesEggers

  I've been diving more and more into Node.js and hosting services like Heroku and Nodejitsu recently and have been trying to figure out how to best deploy database changes for postgres or mysql. There are a few migration projects under npm that I can see; however, all seem to be really buggy or just not work. I currently manage the Monarch migration project on npm, but it's currently buggy itself and my experiences developing such utilities are in other, more procedural, languages. So what do people use to deploy changes to their databases on these environments? What has worked for people? I'm looking for a better understanding of what the current situation/process looks like.

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• Is it safe to set MySQL isolation to "Read Uncommitted" (dirty reads) for typical Web usage? Even with replication?

  - by Continuation

  I'm working on a website with typical CRUD web usage pattern: similar to blogs or forums where users create/update contents and other users read the content. Seems like it's OK to set the database's isolation level to "Read Uncommitted" (dirty reads) in this case. My understanding of the general drawback of "Read Uncommitted" is that a reader may read uncommitted data that will later be rollbacked. In a CRUD blog/forum usage pattern, will there ever be any rollback? And even if there is, is there any major problem with reading uncommitted data? Right now I'm not using any replication, but in the future if I want to use replication (row-based, not statement-based) will a "Read Uncommitted" isolation level prevent me from doing so? What do you think? Has anyone tried using "Read Uncommitted" on their RDBMS?

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• Is it better to use a Database or a data structure for network stack?

  - by poly

  I've built a multi threaded messaging application in C and I'm currently using a MySQL Memory table to save the session ID, but I'm not sure whether this was a good decision or not. It works like this, the application sends a message and saves the source session ID in the MySQL table. When the application gets the success response it will remove the session's ID from the MySQL table, or if it received an error response then it will keep the ID to be retried later. I've built it this way so that I don't need to care about building a data structure by myself, and the Database provides flexibility when it comes to querying it. Do you think this is appropriate or do I need to use something else? Please note that the application is expecting to handle a large number of transactions/sec.

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• Designing a user-defined list to be stored in a relational database - Should I include user index?

  - by Zaemz

  By index, I mean, as the user creates the list, each item receives an integer index for its place in that particular list. Since there will be a table of ListItems, I'd prefer to avoid using the name "Index" for the field. Then I was thinking - should I even include the list index in the database? I figured I would because the list would be created in the same fashion every time, then. Or I could order the list for the user based on its actual primary key, since the list items are created in succession anyway... What should I do?

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• Is there anyway i can create an intranet request form and have it be stored in a database? [on hold]

  - by eternalearth888

  I am trying to create a form for my companies intraNet site. The idea is as follows: An employee wants to make a purchase, so they will go to the appropriate page in the intraNet They will fill out the form on the intraNet page They click the email button The data in the form is saved in a database, and an email is sent to me stating that there is purchase order request form filled out I am not exactly sure how to go about this. Part of me wants to create it in a Data Access Page but I am not sure that's correct. If there is no one here who can help, is there anyone who can direct me to someone/something that can help me?

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• 2012?6?20?(?):?????Oracle Database Appliance????Enterprise Edition???????

  - by Yusuke.Yamamoto

  Oracle Database Appliance????Enterprise Edition??????~Enterprise Edition?????????????????!~ Oracle Database Enterprise Edition ??? ??????????? ????????????? ??????????????????????????! Oracle Database Enterprise Edition ????????????????????????????Oracle Database Appliance ??????????????????????????????????? ????? 2???RAC?!? Oracle Database Appliance??????? Oracle Database11g Release2 RAC One Node???? ??????????????OracleDB??????????? ???? ??:2012?6?20?(?) 13:30~16:30(????:13:00~) ??:????????? 3? ??:???????? ??:???????????????HBA ???:?? ?????·?????? Oracle Database Appliance????Enterprise Edition??????

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• ??????????? Database Firewall ??????????

  - by ???02

  ??????????? Database Firewall ??????????SQL?????????????????SQL????????????WEB?????HTTP??????SQL??????????????????????????????????????????????SQL????????????????WEB??????????????????????????????????SQL??????????????????????Oracle Database Firewall????????????????????SQL?????SQL?????????·???????????????????????????????????Databese Firewall ???????????????Oracle Database Firewall???????????????????????????????·??SQL???????????????·Database ?????????????????·SQL??????Database??????·????·?????????????????????·Oracle Database Firewall ???????Oracle Databese Firewall ?????????? ?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????_DBFW????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????? ???????????????·?????????????????????3?????????????·???????????????????????????????????????????????????????????? ·???????????????????90?????????????????????????????????????????????????????·????????????????????????????????????????????????? ·???????????????????????????????????????????????????????????????????????????????????????????????????????? Web????????????????????????????????????1~4????????????????????———?????———?????????????? 1.????????? : 2.??????(????) : 3.??????(????) : 4.??????? :———?????———?????????????? 1.????????? : ????????????????2.??????(????) :         2011?11?15? 13:00-14:303.??????(????) :         2011?11?17? 15:00-16:304.??????? : ?????????????? ???????????????????????????? ?????? Oracle Direct

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• Best approach for Java/Maven/JPA/Hibernate build with multiple database vendor support?

  - by HDave

  I have an enterprise application that uses a single database, but the application needs to support mysql, oracle, and sql*server as installation options. To try to remain portable we are using JPA annotations with Hibernate as the implementation. We also have a test-bed instance of each database running for development. The app is building nicely in Maven, and I've played around with the hibernate3-maven-plugin and can auto-generate DDL for a given database dialect. What is the best way to approach this so that individual developers can easily test against all three databases and our Hudson based CI server can build things propertly. More specifically: 1) I thought the hbm2ddl goal in the hibernate3-maven-plugin would just generate a schema file, but apparently it connects to a live database and attempts to create the schema. Is there a way to have this just create the schema file for each database dialect without connecting to a database? 2) If the hibernate3-maven-plug insists on actually creating the database schema, is there a way to have it drop the database and recreate it before creating the schema? 3) I am thinking that each developer (and the hudson build machine) should have their own separate database on each database server. Is this typical? 4) Will developers have to run Maven three times...once for each database vendor? If so, how do I merge the results on the build machine? 5) There is a hbm2doc goal within hibernate3-maven-plugin. It seems overkill to run this three times...I gotta believe it'd be nearly identical for each database.

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• Entity Framework 4 "Generate Database from Model" to SQLEXPRESS mdf results in "Could not locate ent

  - by InfinitiesLoop

  I'm using Visual Studio 2010 RTM. I want to do model-first, so I started a new MVC app and added a new blank edmx. Created a few entities. No problem. Then I "Generate Database from Model", and allow the dialog to create a new database for me, which it does successfully as 'mydatabase.mdf' in the app's App_Data directory. Then I open the generated sql file (in Visual Studio). To run it of course I have to give it a connection. I am not sure if it's right, but I used '.\SQLEXPRESS' and Windows authentication. No idea how I'd tell it where the MDF is. Then the problem -- upon executing it, I get: Msg 911, Level 16, State 1, Line 1 Could not locate entry in sysdatabases for database 'mydatabase'. No entry found with that name. Make sure that the name is entered correctly. And indeed there were no tables created in the MDF. So... what am I doing wrong, or am I off my rocker expecting this to work? :)

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• Database Change Management - Setup for Initial Create Scripts, Subsequent Migration Scripts

  - by Martin Aatmaa

  I've got a database change management workflow in place. It's based on SQL scripts (so, it's not a managed code-based solution). The basic setup looks like this: Initial/ Generate Initial Schema.sql Generate Initial Required Data.sql Generate Initial Test Data.sql Migration 0001_MigrationScriptForChangeOne.sql 0002_MigrationScriptForChangeTwo.sql ... The process to spin up a database is to then run all the Initlal scripts, and then run the sequential Migration scripts. A tool takes case of the versioning requirements, etc. My question is, in this kind of setup, is it useful to also maintain this: Current/ Stored Procedures/ dbo.MyStoredProcedureCreateScript.sql ... Tables/ dbo.MyTableCreateScript.sql ... ... By "this" I mean a directory of scripts (separated by object type) that represents the create scripts for spinning up the current/latest version of the database. For some reason, I really like the idea, but I can't concretely justify it's need. Am I missing something? The advantages would be: For dev and source control, we would have the same object-per-file setup that we're used to For deployment, we can spin up a new DB instance to the latest version either by running the Initial+Migrate, or by running the scripts from Current/ For dev, we do not need a DB instance running in order to do development. We can do "offline" development on the Current/ folder. The disadvantages would be: For each change, we need to update the scripts in the Current/ folder, as well as create a Migration script (in the Migration/ folder) Thanks in advance for any input!

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• MySQL Relational Database Foreign Key

  - by user623879

  To learn databasing, I am creating a movie database. To associate multiple directors with a movie, I have the following schema: movie(m_ID, ....) m_director(dirID, dirName)//dirID is a autoincrement primary key m_directs(dirID, m_ID) //dirID, m_ID are set as foreign Keys in the mysql database(InnoDB engine) I have a program that connects to the db that needs to add a movie to the database. I can easily add a new entry to the movie table and the m_director table, but I am having trouble adding a entry in the m_directs table. INSERT INTO m_director (dirName) VALUES("Jason Reitman"); INSERT INTO m_directs (dirID, m_ID) VALUES(LAST_INSERT_ID(), "tt0467406"); I am using this sql statement to insert a new director and add the association to the movie. I know the primary key of the movie, but I don't know the dirID, so I use LAST_INSERT_ID() to get the last id of the director just inserted. The problem I am having is that I get the following error: MySql.Data.MySqlClient.MySqlException (0x80004005): Cannot add or update a child row: a foreign key constraint fails (`siteproducts`. `m_directs`, CONSTRAINT `m_directs_ibfk_2` FOREIGN KEY (`dirID`) REFERENCES `m_directs` (`dirID`) ON DELETE CASCADE ON UPDATE CASCADE) Any ideas?

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• Get id when inserting new row using TableAdapter.Update on a file based database

  - by phq

  I have a database table with one field, called ID, being an auto increment integer. Using a TableAdapter I can read and modify existing rows as well as create new ones. However if I try to modify a newly inserted row I get an DBConcurrencyException: OleDbConnection conn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Shift.mdb;Persist Security Info=True"); ShiftDataSetTableAdapters.ShiftTableAdapter shiftTA = new ShiftDataSetTableAdapters.ShiftTableAdapter(); shiftTA.Connection = conn; ShiftDataSet.ShiftDataTable table = new ShiftDataSet.ShiftDataTable(); ShiftDataSet.ShiftRow row = table.NewShiftRow(); row.Name = "life"; table.Rows.Add(row); shiftTA.Update(row); // row.ID == -1 row.Name = "answer"; // <-- all fine up to here shiftTA.Update(row); // DBConcurrencyException: 0 rows affected Separate question, is there any static type of the NewShiftRow() method I can use so that I don't have to create table everytime I want to insert a new row. I guess the problem in the code comes from row.ID that is still -1 after the first Update() call. The Insert is successful and in the database the row has a valid value of ID. How can I get that ID so that I can continue with the second Update call? Update: IT looks like this could have been done automatically using this setting. However according to the answer on msdn social, OLEDB drivers do not support this feature. Not sure where to go from here, use something else than oledb? Update: Tried SQLCompact but discovered that it had the same limitation, it does not support multiple statements. Final question: is there any simple(single file based) database that would allow you to get the values of a inserted row.

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• SQL Server 2005 database design - many-to-many relationships with hierarchy

  - by Remnant

  Note I have completely re-written my original post to better explain the issue I am trying to understand. I have tried to generalise the problem as much as possible. Also, my thanks to the original people who responded. Hopefully this post makes things a little clearer. Context In short, I am struggling to understand the best way to design a small scale database to handle (what I perceive to be) multiple many-to-many relationships. Imagine the following scenario for a company organisational structure: Textile Division Marketing Division | | ---------------------- ---------------------- | | | | HR Dept Finance Dept HR Dept Finance Dept | | | | ---------- ---------- ---------- --------- | | | | | | | | Payroll Hiring Audit Tax Payroll Hiring Audit Accounts | | | | | | | | Emps Emps Emps Emps Emps Emps Emps Emps NB: Emps denotes a list of employess that work in that area When I first started with this issue I made four separate tables: Divisions - Textile, Marketing (PK = DivisionID) Departments - HR, Finance (PK = DeptID) Functions - Payroll, Hiring, Audit, Tax, Accounts (PK = FunctionID) Employees - List of all Employees (PK = EmployeeID) The problem as I see it is that there are multiple many-to-many relationships i.e. many departments have many divisions and many functions have many departments. Question Giving the database structure above, suppose I wanted to do the following: Get all employees who work in the Payroll function of the Marketing Division To do this I need to be able to differentiate between the two Payroll departments but I am not sure how this can be done? I understand that I could build a 'Link / Junction' table between Departments and Functions so that I can retrieve which Functions are in which Departments. However, I would still need to differentiate the Division they belong to. Research Effort As you can see I am an abecedarian when it comes to database deisgn. I have spent the last two days resaerching this issue, traversing nested set models, adjacency models, reading that this issue is known not to be NP complete etc. I am sure there is a simple solution?

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• Get data from database without refresh whole page

  - by stefanz

  Hello everybody. My project is about a school admin I have a page called : createClass.php, where user inserts grade, profile etc. When he press "submit" page called createdClass.php is loading. Inside this page I have all code which insert data into database and also an "if" structure which says : "Class already exists" if in database is another class with same specifications. Also in second page (createdClass.php) i have a small table which shows the place of each student. First time all cells are green (this means that place is free) and if i click one of them appear a popup window which let me to add info about student from that place. If a place is busy the cell will be red (take a look here : http://screencast.com/t/NzM2YzYxNjct). The big problem is that the cell will be red only after refresh the page (the place ask for data from database). If I press refresh appears "class already exists". To test the code i added in a comment all lines which verify and add respectively classroom . I think my problem can be solved with ajax. I'm waiting for an answer. Regards Stefan

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• Database design for credit based purchases

  - by FreshCode

  I need an elegant way to implement credit-based purchases for an online store with a small variety of products which can be purchased using virtual credit or real currency. Alternatively, products could only be priced in credits. Previous work I have implemented credit-based purchasing before using different product types (eg. Credit, Voucher or Music) with post-order processing to assign purchased credit to users in the form of real currency, which could subsequently be used to discount future orders' charge totals. This worked fairly well as a makeshift solution, but did not succeed in disconnecting the virtual currency from the real currency, which is what I'd like to do, since spending credits is psychologically easier for customers than spending real currency. Design I need guidance on designing the database correctly with support for the simultaneous bulk purchase of credits at a discount along with real currency products. Alternatively, should all products be priced in credits and only credit have a real currency value? Existing Database Design Partial Products table: ProductId Title Type UnitPrice SalePrice Partial Orders table: OrderId UserId (related to Users table, not shown) Status Value Total Partial OrderItems table (similar to CartItems table): OrderItemId OrderId (related to Orders table) ProductId (related to Products table) Quantity UnitPrice SalePrice Prospective UserCredits table: CreditId UserId (related to Users table, not shown) Value (+/- value. Summed over time to determine saldo.) Date I'm using ASP.NET MVC and LINQ-to-SQL on a SQL Server database.

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• PHP - Database schema: version control, branching, migrations.

  - by Billiam

  I'm trying to come up with (or find) a reusable system for database schema versioning in php projects. There are a number of Rails-style migration projects available for php. http://code.google.com/p/mysql-php-migrations/ is a good example. It uses timestamps for migration files, which helps with conflicts between branches. General problem with this kind of system: When development branch A is checked out, and you want to check out branch B instead, B may have new migration files. This is fine, migrating to newer content is straight forward. If branch A has newer migration files, you would need to migrate downwards to the nearest shared patch. If branch A and B have significantly different code bases, you may have to migrate down even further. This may mean: Check out B, determine shared patch number, check out A, migrate downwards to this patch. This must be done from A since the actual applied patches are not available in B. Then, checkout branch B, and migrate to newest B patch. Reverse process again when going from B to A. Proposed system: When migrating upwards, instead of just storing the patch version, serialize the whole patch in database for later use, though I'd probably only need the down() method. When changing branches, compare patches that have been run to patches that are available in the destination branch. Determine nearest shared patch (or oldest difference, maybe) between db table of run patches and patches in destination branch by ID or hash. Could also look for new or missing patches that are buried under a number of shared patches between the two branches. Automatically merge down to the nearest shared patch, using the db table stored down() methods, and then merge up to the branche's latest patch. My question is: Is this system too crazy and/or fraught with consequences to bother developing? My experience with database schema versioning is limited to PHP autopatch, which is an up()-only system requiring filenames with sequential IDs.

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• Using PHP to display button with hyperlink or greyed out button if no URL in database

  - by Diane

  I've got a webpage that I'm working on where you click on a letter or category and it displays records matching that query from a database. One of the things I want to display is a hyperlinked button that says "Website" if the database record contains a URL in the 'URL' field, and if there is no value in that field, it will display a greyed out version of that button. I tried using an if...else statement, but was absolutely unable to get the syntax correct trying to get php to call up the 'URL' value in the middle of an "echo " So here's what I did: <?php if($row_rsmemalpha['URL'] != NULL) ?><a href="http://<?php echo ($row_rsmemalpha['URL']);?>"><target ="_blank"><img src="web_button_on.gif" alt="Website" border="0" height="18" width="103" /></target></a> <?php if($row_rsmemalpha['URL'] == NULL) echo "<img src=\"web_button_off.gif\" alt=\"No Website Available\" height=\"18\" width=\"103\" />"; ?> If there is a URL available it shows the button properly. But if there isn't a URL in the database it shows both buttons. I have spent a few days studying examples and tutorials on the web, but haven't found too much that helps. The buttons were completely non-functional when I started, so I'm pretty proud of getting this far with it! I've just run out of time and patience for more trial-and-error experimenting. Any help is appreciated... Diane

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• Images in database vs file system

  - by Jesse

  We have a project coming up where we will be building a whole backend CMS system that will power our entire extranet and intranet with one package. The question I have been trying to find an answer to is which is better: storing images in the database (SQL Server 2005) so we may have integrity, single replication plan, etc OR storing on the file system? One issue we have is that we have multiple servers load balanced that require to have the same data at all times. As of now we have SQL replication taking care of that but file replication seems to be a little tougher. Another concern we have is that we would like to have multiple resolutions of the same image, we are not sure if creating and storing each version on the file system would be best or maybe dynamically pulling and creating the resolution image we would like upon request. Our concerns are the with the following: Data integrity Data replication Multiple resolutions Speed of database vs file system Overhead load of database vs file system Data management and backup Does anyone have a similar situation or have any input on what would be recommended? Thanks in advance for the help!

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• When optimizing database queries, what exactly is the relationship between number of queries and siz

  - by williamjones

  To optimize application speed, everyone always advises to minimize the number of queries an application makes to the database, consolidating them into fewer queries that retrieve more wherever possible. However, this also always comes with the caution that data transferred is still data transferred, and just because you are making fewer queries doesn't make the data transferred free. I'm in a situation where I can over-include on the query in order to cut down the number of queries, and simply remove the unwanted data in the application code. Is there any type of a rule of thumb on how much of a cost there is to each query, to know when to optimize number of queries versus size of queries? I've tried to Google for objective performance analysis data, but surprisingly haven't been able to find anything like that. Clearly this relationship will change for factors such as when the database grows in size, making this somewhat individualized, but surely this is not so individualized that a broad sense of the landscape can't be drawn out? I'm looking for general answers, but for what it's worth, I'm running an application on Heroku.com, which means Ruby on Rails with a Postgres database.

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• MySQL database design question

  - by Greelmo

  I'm trying to weigh the pros and cons of a database design, and would like to get some feedback as to the best approach. Here is the situation: I have users of my system that have only a few required items (username, password). They can then supply a lot of optional information. This optional information continues to grow as the system grows, so I want to do it in such a way that adding new optional information is easy. Currently, I have a separate table for each piece of information. For example, there's a table called 'names' that holds 'user_id', 'first_name', and 'last_name'. There's 'address', 'occupation', etc. You get the drift. In most cases, when I talk to my database, I'm looking only for users with one particular qualifier (name, address, etc.). However, there are instances when I want to see what information a user has set. The 'edit account' page, for example, must run queries for each piece of information it wants. Is this wasteful? Is there a way I can structure my queries or my database to make it so I never have to do one query for each piece of information like that without getting my tables to huge? If i want to add 'marital status', how hard will that be if I don't have a one-table-per-attribute system? Thanks in advance.

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• Entity Framework - refresh objects from database

  - by Nebo

  I'm having trouble with refreshing objects in my database. I have an two PC's and two applications. On the first PC, there's an application which communicates with my database and adds some data to Measurements table. On my other PC, there's an application which retrives the latest Measurement under a timer, so it should retrive measurements added by the application on my first PC too. The problem is it doesn't. On my application start, it caches all the data from database and never get new data added. I use Refresh() method which works well when I change any of the cached data, but it doesn't refresh newly added data. Here is my method which should update the data: public static Entities myEntities = new Entities(); public static Measurement GetLastMeasurement(int conditionId) { myEntities.Refresh(RefreshMode.StoreWins, myEntities.Measurements); return (from measurement in myEntities.Measurements where measurement.ConditionId == conditionId select measurement).OrderByDescending(cd => cd.Timestamp).First(); } P.S. Applications have different connection strings in app.config (different accounts for the same DB).

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• PHP Database connection practice

  - by Phill Pafford

  I have a script that connects to multiple databases (Oracle, MySQL and MSSQL), each database connection might not be used each time the script runs but all could be used in a single script execution. My question is, "Is it better to connect to all the databases once in the beginning of the script even though all the connections might not be used. Or is it better to connect to them as needed, the only catch is that I would need to have the connection call in a loop (so the database connection would be new for X amount of times in the loop). Yeah Example Code #1: // Connections at the beginning of the script $dbh_oracle = connect2db(); $dbh_mysql = connect2db(); $dbh_mssql = connect2db(); for ($i=1; $i<=5; $i++) { // NOTE: might not use all the connections $rs = queryDb($query,$dbh_*); // $dbh can be any of the 3 connections } Yeah Example Code #2: // Connections in the loop for ($i=1; $i<=5; $i++) { // NOTE: Would use all the connections but connecting multiple times $dbh_oracle = connect2db(); $dbh_mysql = connect2db(); $dbh_mssql = connect2db(); $rs_oracle = queryDb($query,$dbh_oracle); $rs_mysql = queryDb($query,$dbh_mysql); $rs_mssql = queryDb($query,$dbh_mssql); } now I know you could use a persistent connection but would that be one connection open for each database in the loop as well? Like mysql_pconnect(), mssql_pconnect() and adodb for Oracle persistent connection method. I know that persistent connection can also be resource hogs and as I'm looking for best performance/practice.

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• Database Functional Programming in Clojure

  - by Ralph

  "It is tempting, if the only tool you have is a hammer, to treat everything as if it were a nail." - Abraham Maslow I need to write a tool to dump a large hierarchical (SQL) database to XML. The hierarchy consists of a Person table with subsidiary Address, Phone, etc. tables. I have to dump thousands of rows, so I would like to do so incrementally and not keep the whole XML file in memory. I would like to isolate non-pure function code to a small portion of the application. I am thinking that this might be a good opportunity to explore FP and concurrency in Clojure. I can also show the benefits of immutable data and multi-core utilization to my skeptical co-workers. I'm not sure how the overall architecture of the application should be. I am thinking that I can use an impure function to retrieve the database rows and return a lazy sequence that can then be processed by a pure function that returns an XML fragment. For each Person row, I can create a Future and have several processed in parallel (the output order does not matter). As each Person is processed, the task will retrieve the appropriate rows from the Address, Phone, etc. tables and generate the nested XML. I can use a a generic function to process most of the tables, relying on database meta-data to get the column information, with special functions for the few tables that need custom processing. These functions could be listed in a map(table name -> function). Am I going about this in the right way? I can easily fall back to doing it in OO using Java, but that would be no fun. BTW, are there any good books on FP patterns or architecture? I have several good books on Clojure, Scala, and F#, but although each covers the language well, none look at the "big picture" of function programming design.

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