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AR queying guide: let limit and offset be different numbers to help making clear what is what in the explanation, rewords also a bit

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Xavier Noria 2010-07-14 13:17:01 +02:00
parent 438bff6ccd
commit 5994567839
1 changed files with 6 additions and 6 deletions
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12
railties/guides/source/active_record_querying.textile
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@ -447,28 +447,28 @@ h4. Limit and Offset
To apply +LIMIT+ to the SQL fired by the +Model.find+, you can specify the +LIMIT+ using +limit+ and +offset+ methods on the relation.
You can use +limit+ to specify the number of records to be retrieved, and use +offset+ to specify the number of records to skip before starting to return the records. For example:
You can use +limit+ to specify the number of records to be retrieved, and use +offset+ to specify the number of records to skip before starting to return the records. For example
<ruby>
Client.limit(5)
</ruby>
This code will return a maximum of 5 clients and because it specifies no offset it will return the first 5 clients in the table. The SQL it executes will look like this:
will return a maximum of 5 clients and because it specifies no offset it will return the first 5 in the table. The SQL it executes looks like this:
<sql>
SELECT * FROM clients LIMIT 5
</sql>
Or chaining both +limit+ and +offset+:
Adding +offset+ to that
<ruby>
Client.limit(5).offset(5)
Client.limit(5).offset(30)
</ruby>
This code will return a maximum of 5 clients beginning with the 6th client in the clients table, skipping the first five clients as specified by the offset. The SQL looks like:
will return instead a maximum of 5 clients beginning with the 31st. The SQL looks like:
<sql>
SELECT * FROM clients LIMIT 5, 5
SELECT * FROM clients LIMIT 5, 30
</sql>
h4. Group