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Where are my postgres *.conf files?
I have recently reinstalled postgresql 8.3 on my Ubuntu 8.04 after update. Used EnterpriseDB package. I can connect to the database locally, I see system DB postgres but I can't configure it because I can't find config files. Searched through entire hard drive and found only samples like pg_hba.con...
Find() vs. Where().FirstOrDefault()
...nd makes use of the primary keys (hence indexes), whereas Where is a plain sql query
– percebus
Feb 9 '16 at 19:56
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When to use SELECT … FOR UPDATE?
...ds on the concurrency control your database system is using.
MyISAM in MySQL (and several other old systems) does lock the whole table for the duration of a query.
In SQL Server, SELECT queries place shared locks on the records / pages / tables they have examined, while DML queries place update lo...
How to access a dictionary element in a Django template?
...de in your templates and vice-versa.
I'd try the above method and see what SQL the ORM generates as I'm not sure off the top of my head if it will pre-cache the properties and just create a subselect for the property or if it will iteratively / on-demand run the query to calculate vote count. But if...
淘宝大秒系统设计详解 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...的数据大部分都是热数据，比如会启用单独cache集群或MySQL数据库来放热点数据，目前也是不想0.01%的数据影响另外99.99%。
当然实现隔离很有多办法，如可以按照用户来区分，给不同用户分配不同cookie，在接入层路由到不同服...
How to select all records from one table that do not exist in another table?
...in basically every database engine ever that attempts to implement ANSI 92 SQL
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Multiline string literal in C#
...whatever line break your source has them as) into the string, however. For SQL, that's not only harmless but probably improves the readability anywhere you see the string - but in other places it may not be required, in which case you'd either need to not use a multi-line verbatim string literal to ...
What is the actual use of Class.forName(“oracle.jdbc.driver.OracleDriver”) while connecting to a dat
...ing the method Class.forName. This methods required an object of type java.sql.Driver. Each JDBC driver contains one or more classes that implements the interface java.sql.Driver.
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Any JDBC 4.0 drivers that are found in your class path are automatically loaded. (However, you must manually load an...
Visual Studio appears to randomly adopt American keyboard layout
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I've definitely had an occasion where SQL Server Management Studio (based on Visual Studio) adopted US keyboard layout for no apparent reason but all other applications were on UK layout so this wasn't a global Windows settings for me.
– Mar...
Creating a copy of a database in PostgreSQL [closed]
...s, and select "New Database". One of the options is the template, and the SQL used to create the database is equivalent. It is so much faster than a dump / restore on the same server.
– jwhitlock
Jun 17 '11 at 15:19
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