diff options
Diffstat (limited to 'railties/guides/source')
-rw-r--r-- | railties/guides/source/active_record_querying.textile | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/railties/guides/source/active_record_querying.textile b/railties/guides/source/active_record_querying.textile index beada85ce3..5970a45839 100644 --- a/railties/guides/source/active_record_querying.textile +++ b/railties/guides/source/active_record_querying.textile @@ -692,6 +692,17 @@ Item.transaction do end </ruby> +If you already have an instance of your model, you can start a transaction and acquire the lock in one go using the following code: + +<ruby> +item = Item.first +item.with_lock do + # This block is called within a transaction, + # item is already locked. + item.increment!(:views) +end +</ruby> + h3. Joining Tables Active Record provides a finder method called +joins+ for specifying +JOIN+ clauses on the resulting SQL. There are multiple ways to use the +joins+ method. |