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how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...skipped if it would violate a primary/unique key constraint. For instance, MySQL has INSERT IGNORE .
11 Answers
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INSERT … ON DUPLICATE KEY (do nothing)
... uses resources for the second action.
Use INSERT IGNORE ...,
Negative : MySQL will not show any errors if something goes wrong, so you cannot handle the errors. Use it only if you don’t care about the query.
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“use database_name” command in PostgreSQL
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If I'm not mistaken, databases in MySQL are more akin to schemas in PostgreSQL -- you can switch between those, but DBs in PostgreSQL are a whole different ballgame.
– mpen
May 10 '12 at 3:40
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How do you do a limit query in JPQL or HQL?
In Hibernate 3, is there a way to do the equivalent of the following MySQL limit in HQL?
14 Answers
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How to find the lowest common ancestor of two nodes in any binary tree?
...ible. For both nodes in question construct a list containing the path from root to the node by starting at the node, and front inserting the parent.
So for 8 in your example, you get (showing steps): {4}, {2, 4}, {1, 2, 4}
Do the same for your other node in question, resulting in (steps not shown...
How to switch databases in psql?
In MySQL , I used use database_name;
12 Answers
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SQL Server - inner join when updating [duplicate]
...it works with UDPATE SET FROM JOIN WHERE? Does it depend on the version of mysql?
– Farside
Apr 28 '16 at 12:45
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GUI Tool for PostgreSQL [closed]
...t to know is there any GUI Tool for PostgreSQL just like SQLYog for MySql
2 Answers
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SQL: How to perform string does not equal
... Just noticed that the <=> operator only exists in the MySQL world, for more info see what is <=>
– Top-Master
Apr 27 '19 at 6:18
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Oracle取前N条记录方法 Oracle实现SELECT TOP N的方法 - 数据库(内核) - 清...
...from tablexxx order by xxx desc ) where rownum <= Noracle数据库不支持mysql中limit, top功...select * from ( select * from tablexxx order by xxx desc ) where rownum <= N
oracle数据库不支持mysql中limit, top功能,但可以通过rownum来限制返回的结果集的行数,rownum并不...