Merge pull request rails#53029 from jgsheppa/52852_nulls_not_distinct_documentation

fatkodima · web-flow · commit 5ff57a5e909e · 2024-09-24T20:39:52.000+03:00
Add documentation for `nulls_not_distinct` option to `add_index` [ci skip]
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
@@ -855,6 +855,16 @@ def rename_column(table_name, column_name, new_column_name)
       #
       # Note: only supported by PostgreSQL.
       #
+      # ====== Creating an index where NULLs are treated equally
+      #
+      #   add_index(:people, :last_name, nulls_not_distinct: true)
+      #
+      # generates:
+      #
+      #   CREATE INDEX index_people_on_last_name ON people (last_name) NULLS NOT DISTINCT
+      #
+      # Note: only supported by PostgreSQL version 15.0.0 and greater.
+      #
       # ====== Creating an index with a specific method
       #
       #   add_index(:developers, :name, using: 'btree')

Original file line number	Diff line number	Diff line change
`@@ -855,6 +855,16 @@ def rename_column(table_name, column_name, new_column_name)`
`855`	`855`	`#`
`856`	`856`	`# Note: only supported by PostgreSQL.`
`857`	`857`	`#`
	`858`	`+ # ====== Creating an index where NULLs are treated equally`
	`859`	`+ #`
	`860`	`+ # add_index(:people, :last_name, nulls_not_distinct: true)`
	`861`	`+ #`
	`862`	`+ # generates:`
	`863`	`+ #`
	`864`	`+ # CREATE INDEX index_people_on_last_name ON people (last_name) NULLS NOT DISTINCT`
	`865`	`+ #`
	`866`	`+ # Note: only supported by PostgreSQL version 15.0.0 and greater.`
	`867`	`+ #`
`858`	`868`	`# ====== Creating an index with a specific method`
`859`	`869`	`#`
`860`	`870`	`# add_index(:developers, :name, using: 'btree')`