diff options
Diffstat (limited to 'railties')
| -rw-r--r-- | railties/guides/source/active_record_querying.textile | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/railties/guides/source/active_record_querying.textile b/railties/guides/source/active_record_querying.textile index 5264477e1c..1da12cbc9b 100644 --- a/railties/guides/source/active_record_querying.textile +++ b/railties/guides/source/active_record_querying.textile @@ -337,6 +337,32 @@ This code will generate SQL like this: SELECT * FROM clients WHERE (clients.orders_count IN (1,3,5)) </sql> +h4. +arel_table+ + +The +arel_table+ method is used in the following sections to gain access to more advanced functionality of the Active Relation building language. You may see examples such as this: + +<ruby> +Post.where(Post.arel_table[:comments_count].eq(5))) +</ruby> + +Don't be alarmed! This method returns an +Arel::Table+ object which provides methods for accessing fields and building queries, as you'll see in the following sections. + +h4. +eq+ + +The +eq+ method can be used to check if a field is a specific value: + +<ruby> +Post.where(Post.arel_table[:comments_count].eq(5)) +</ruby> + +h4. +eq_any+ + +The +eq_any+ method can be used to return objects of a relation that have the specified field matching any of the specified values. + +<ruby> +Post.where(Post.arel_table[:comments_count].eq_any([1,2]) +</ruby> + h3. Ordering To retrieve records from the database in a specific order, you can use the +order+ method. |