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Correct use of flush() in JPA/Hibernate
...n-dependent.
In general anyway, JPA providers like Hibernate can cache the SQL instructions they are supposed to send to the database, often until you actually commit the transaction.
For example, you call em.persist(), Hibernate remembers it has to make a database INSERT, but does not actually exec...
How can I get column names from a table in Oracle?
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In SQL Server...
SELECT [name] AS [Column Name]
FROM syscolumns
WHERE id = (SELECT id FROM sysobjects WHERE type = 'V' AND [Name] = 'Your table name')
Type = 'V' for views
Type = 'U' for tables
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postgresql - sql - count of `true` values
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Since PostgreSQL 9.4 there's the FILTER clause, which allows for a very concise query to count the true values:
select count(*) filter (where myCol)
from tbl;
The above query is a bad example in that a simple WHERE clause would suffice...
What Java ORM do you prefer, and why? [closed]
...t queries have low overhead and I can fit lots of complex logic into large SQL queries, and shift a lot of my processing into the database.
So consider just using the JDBC package.
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Command line: piping find results to rm
I'm trying to work out a command which deletes sql files older than 15 days.
4 Answers
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How do you use variables in a simple PostgreSQL script?
For example, in MS-SQL, you can open up a query window and run the following:
10 Answers
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Using varchar(MAX) vs TEXT on SQL Server
...GB of char data) is the recommended replacement for the TEXT datatype in SQL Server 2005 and Next SQL SERVER versions.
5...
How to shrink/purge ibdata1 file in MySQL
I am using MySQL in localhost as a "query tool" for performing statistics in R, that is, everytime I run a R script, I create a new database (A), create a new table (B), import the data into B, submit a query to get what I need, and then I drop B and drop A.
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2016电商“死亡”名单（上半年） - 资讯 - 清泛网 - 专注IT技能提升
...业务曾扩展至北京、深圳、杭州等十多个城市，合作品牌包括赛百味、黄太吉等；2016年1月低调转型，上线电商平台最鲜到商城，通过众包物流与众包仓储相结合的方式提供“冷链存储”和“生鲜宅配”服务。
融资记录：A轮...
What is your naming convention for stored procedures? [closed]
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Here's some clarification about the sp_ prefix issue in SQL Server.
Stored procedures named with the prefix sp_ are system sprocs stored in the Master database.
If you give your sproc this prefix, SQL Server looks for them in the Master database first, then the context database,...