pg, `create_schema`, `drop_schema` and `rename_table` quote schema name.

Closes #21418.

Previously schema names were not quoted. This leads to issues when a
schema names contains a ".". Methods in `schema_statements.rb` should
quote user input.

2 files changed, 8 insertions, 3 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb b/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
index f175730551..d5879ea7df 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
@@ -31,6 +31,11 @@ module ActiveRecord
           Utils.extract_schema_qualified_name(name.to_s).quoted
         end
 
+        # Quotes schema names for use in SQL queries.
+        def quote_schema_name(name)
+          PGconn.quote_ident(name)
+        end
+
         def quote_table_name_for_assignment(table, attr)
           quote_column_name(attr)
         end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
index 21268b63b1..a3fc8fbc51 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
@@ -210,12 +210,12 @@ module ActiveRecord
 
         # Creates a schema for the given schema name.
         def create_schema schema_name
-          execute "CREATE SCHEMA #{schema_name}"
+          execute "CREATE SCHEMA #{quote_schema_name(schema_name)}"
         end
 
         # Drops the schema for the given schema name.
         def drop_schema(schema_name, options = {})
-          execute "DROP SCHEMA#{' IF EXISTS' if options[:if_exists]} #{schema_name} CASCADE"
+          execute "DROP SCHEMA#{' IF EXISTS' if options[:if_exists]} #{quote_schema_name(schema_name)} CASCADE"
         end
 
         # Sets the schema search path to a string of comma-separated schema names.
@@ -376,7 +376,7 @@ module ActiveRecord
             new_seq = "#{new_name}_#{pk}_seq"
             idx = "#{table_name}_pkey"
             new_idx = "#{new_name}_pkey"
-            execute "ALTER TABLE #{quote_table_name(seq)} RENAME TO #{quote_table_name(new_seq)}"
+            execute "ALTER TABLE #{seq.quoted} RENAME TO #{quote_table_name(new_seq)}"
             execute "ALTER INDEX #{quote_table_name(idx)} RENAME TO #{quote_table_name(new_idx)}"
           end