提交 22512a3b 编写于 作者: D dapan1121

enh: corrent slimit/limit statement

上级 e62e125d
......@@ -248,13 +248,13 @@ You can also use the NULLS keyword to specify the position of null values. Ascen
The LIMIT keyword controls the number of results that are displayed. You can also use the OFFSET keyword to specify the result to display first. `LIMIT` and `OFFSET` are executed after `ORDER BY` in the query execution. You can include an offset in a LIMIT clause. For example, LIMIT 5 OFFSET 2 can also be written LIMIT 2, 5. Both of these clauses display the third through the seventh results.
In a statement that includes a PARTITION BY clause, the LIMIT keyword is performed on each partition, not on the entire set of results.
In a statement that includes a PARTITION BY/GROUP BY clause, the LIMIT keyword is performed on each partition/group, not on the entire set of results.
## SLIMIT
The SLIMIT keyword is used with a PARTITION BY clause to control the number of partitions that are displayed. You can include an offset in a SLIMIT clause. For example, SLIMIT 5 OFFSET 2 can also be written LIMIT 2, 5. Both of these clauses display the third through the seventh partitions.
The SLIMIT keyword is used with a PARTITION BY/GROUP BY clause to control the number of partitions/groups that are displayed. You can include an offset in a SLIMIT clause. For example, SLIMIT 5 OFFSET 2 can also be written LIMIT 2, 5. Both of these clauses display the third through the seventh partitions/groups.
Note: If you include an ORDER BY clause, only one partition can be displayed.
Note: If you include an ORDER BY clause, only one partition/group can be displayed.
## Special Query
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......@@ -248,11 +248,11 @@ NULLS 语法用来指定 NULL 值在排序中输出的位置。NULLS LAST 是升
LIMIT 控制输出条数,OFFSET 指定从第几条之后开始输出。LIMIT/OFFSET 对结果集的执行顺序在 ORDER BY 之后。LIMIT 5 OFFSET 2 可以简写为 LIMIT 2, 5,都输出第 3 行到第 7 行数据。
在有 PARTITION BY 子句时,LIMIT 控制的是每个切分的分片中的输出,而不是总的结果集输出。
在有 PARTITION BY/GROUP BY 子句时,LIMIT 控制的是每个切分的分片中的输出,而不是总的结果集输出。
## SLIMIT
SLIMIT 和 PARTITION BY 子句一起使用,用来控制输出的分片的数量。SLIMIT 5 SOFFSET 2 可以简写为 SLIMIT 2, 5,都表示输出第 3 个到第 7 个分片。
SLIMIT 和 PARTITION BY/GROUP BY 子句一起使用,用来控制输出的分片的数量。SLIMIT 5 SOFFSET 2 可以简写为 SLIMIT 2, 5,都表示输出第 3 个到第 7 个分片。
需要注意,如果有 ORDER BY 子句,则输出只有一个分片。
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