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MYSQL how to use Limit to limit the number of update lines, many novices are not very clear about this, in order to help you solve this problem, the following editor will explain in detail for you, people with this need can come to learn, I hope you can get something.

To modify the config table, change the is_ok in 5607 rows to true.

I want to implement it through the following sql statement

Sql code

UPDATE channel_config set is_adam_pub=1 where channel_id in (select channel_id from channel_config limit 5607)

Found that Mysql cannot support the use of Limit in clauses, and the database will report an error.

This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery'

Find a method on the Internet, which can support substrings to use Limit

Sql code

UPDATE channel_config set is_adam_pub=1 where channel_id in (select t.channel_id from (select channel_id from channel_config limit 5607) as t)

Although this processing can achieve the effect, but the execution is very slow, using 15.815ms

On second thought, does update also have the use of limit?

Sql code

UPDATE channel_config set is_adam_pub=1 LIMIT 5607

It turned out to be successful, and 0.102ms was used.

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