我如何在Oracle中执行此查询 [英] How can I perform this query in oracle

问题描述

能否请您指导我进行与Oracle中此查询等效的操作:

Can you please guide me to the equivalent to this query in Oracle:

SELECT SQL_CALC_FOUND_ROWS * FROM tableName 

SELECT FOUND_ROWS() as cnt

谢谢

推荐答案

查询从tableName检索所有行，然后在tableName中检索行数.使用SQL_CALC_FOUND_ROWS进行此操作只是性能优化:它使您不必执行两次查询.

The query retrieves all rows from tableName, and then retrieves the number of rows in tableName. Doing that with SQL_CALC_FOUND_ROWS is just a performance optimization: it saves you from doing two queries.

如果性能不是问题，那么Oracle的等效项将是:

If performance is not an issue, an equivalent for Oracle would be:

SELECT * FROM tableName 
SELECT count(*) from tableName

如果您可以重写客户端，则可以在一个查询中同时进行:

If you are in a position to rewrite the client, you could do both in one query:

SELECT  *
,       (SELECT count(*) from tableName) as totalRows
FROM    tableName 

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