Methods
- client_min_messages
- client_min_messages=
- collation
- create_database
- create_schema
- ctype
- current_database
- current_schema
- drop_schema
- encoding
- foreign_keys
- foreign_table_exists?
- foreign_tables
- index_name_exists?
- rename_index
- rename_table
- schema_exists?
- schema_names
- schema_search_path
- schema_search_path=
- serial_sequence
- validate_check_constraint
- validate_constraint
- validate_foreign_key
Instance Public methods
client_min_messages()
Returns the current client message level.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 237
def client_min_messages
query_value("SHOW client_min_messages", "SCHEMA")
end
🔎 See on GitHub
client_min_messages=(level)
Set the client message level.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 242
def client_min_messages=(level)
execute("SET client_min_messages TO '#{level}'", "SCHEMA")
end
🔎 See on GitHub
collation()
Returns the current database collation.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 189
def collation
query_value("SELECT datcollate FROM pg_database WHERE datname = current_database()", "SCHEMA")
end
🔎 See on GitHub
create_database(name, options = {})
Create a new PostgreSQL database. Options include :owner
, :template
, :encoding
(defaults to utf8), :collation
, :ctype
, :tablespace
, and :connection_limit
(note that MySQL
uses :charset
while PostgreSQL uses :encoding
).
Example:
create_database config[:database], config
create_database 'foo_development', encoding: 'unicode'
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 22
def create_database(name, options = {})
options = { encoding: "utf8" }.merge!(options.symbolize_keys)
option_string = options.each_with_object(+"") do |(key, value), memo|
memo << case key
when :owner
" OWNER = \"#{value}\""
when :template
" TEMPLATE = \"#{value}\""
when :encoding
" ENCODING = '#{value}'"
when :collation
" LC_COLLATE = '#{value}'"
when :ctype
" LC_CTYPE = '#{value}'"
when :tablespace
" TABLESPACE = \"#{value}\""
when :connection_limit
" CONNECTION LIMIT = #{value}"
else
""
end
end
execute "CREATE DATABASE #{quote_table_name(name)}#{option_string}"
end
🔎 See on GitHub
create_schema(schema_name)
Creates a schema for the given schema name.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 210
def create_schema(schema_name)
execute "CREATE SCHEMA #{quote_schema_name(schema_name)}"
end
🔎 See on GitHub
ctype()
Returns the current database ctype.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 194
def ctype
query_value("SELECT datctype FROM pg_database WHERE datname = current_database()", "SCHEMA")
end
🔎 See on GitHub
current_database()
Returns the current database name.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 174
def current_database
query_value("SELECT current_database()", "SCHEMA")
end
🔎 See on GitHub
current_schema()
Returns the current schema name.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 179
def current_schema
query_value("SELECT current_schema", "SCHEMA")
end
🔎 See on GitHub
drop_schema(schema_name, **options)
Drops the schema for the given schema name.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 215
def drop_schema(schema_name, **options)
execute "DROP SCHEMA#{' IF EXISTS' if options[:if_exists]} #{quote_schema_name(schema_name)} CASCADE"
end
🔎 See on GitHub
encoding()
Returns the current database encoding format.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 184
def encoding
query_value("SELECT pg_encoding_to_char(encoding) FROM pg_database WHERE datname = current_database()", "SCHEMA")
end
🔎 See on GitHub
foreign_keys(table_name)
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 483
def foreign_keys(table_name)
scope = quoted_scope(table_name)
fk_info = exec_query(<<~SQL, "SCHEMA")
SELECT t2.oid::regclass::text AS to_table, a1.attname AS column, a2.attname AS primary_key, c.conname AS name, c.confupdtype AS on_update, c.confdeltype AS on_delete, c.convalidated AS valid
FROM pg_constraint c
JOIN pg_class t1 ON c.conrelid = t1.oid
JOIN pg_class t2 ON c.confrelid = t2.oid
JOIN pg_attribute a1 ON a1.attnum = c.conkey[1] AND a1.attrelid = t1.oid
JOIN pg_attribute a2 ON a2.attnum = c.confkey[1] AND a2.attrelid = t2.oid
JOIN pg_namespace t3 ON c.connamespace = t3.oid
WHERE c.contype = 'f'
AND t1.relname = #{scope[:name]}
AND t3.nspname = #{scope[:schema]}
ORDER BY c.conname
SQL
fk_info.map do |row|
options = {
column: row["column"],
name: row["name"],
primary_key: row["primary_key"]
}
options[:on_delete] = extract_foreign_key_action(row["on_delete"])
options[:on_update] = extract_foreign_key_action(row["on_update"])
options[:validate] = row["valid"]
ForeignKeyDefinition.new(table_name, row["to_table"], options)
end
end
🔎 See on GitHub
foreign_table_exists?(table_name)
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 518
def foreign_table_exists?(table_name)
query_values(data_source_sql(table_name, type: "FOREIGN TABLE"), "SCHEMA").any? if table_name.present?
end
🔎 See on GitHub
foreign_tables()
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 514
def foreign_tables
query_values(data_source_sql(type: "FOREIGN TABLE"), "SCHEMA")
end
🔎 See on GitHub
index_name_exists?(table_name, index_name)
Verifies existence of an index with a given name.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 68
def index_name_exists?(table_name, index_name)
table = quoted_scope(table_name)
index = quoted_scope(index_name)
query_value(<<~SQL, "SCHEMA").to_i > 0
SELECT COUNT(*)
FROM pg_class t
INNER JOIN pg_index d ON t.oid = d.indrelid
INNER JOIN pg_class i ON d.indexrelid = i.oid
LEFT JOIN pg_namespace n ON n.oid = i.relnamespace
WHERE i.relkind IN ('i', 'I')
AND i.relname = #{index[:name]}
AND t.relname = #{table[:name]}
AND n.nspname = #{index[:schema]}
SQL
end
🔎 See on GitHub
rename_index(table_name, old_name, new_name)
Renames an index of a table. Raises error if length of new index name is greater than allowed limit.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 477
def rename_index(table_name, old_name, new_name)
validate_index_length!(table_name, new_name)
execute "ALTER INDEX #{quote_column_name(old_name)} RENAME TO #{quote_table_name(new_name)}"
end
🔎 See on GitHub
rename_table(table_name, new_name)
Renames a table. Also renames a table's primary key sequence if the sequence name exists and matches the Active Record default.
Example:
rename_table('octopuses', 'octopi')
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 378
def rename_table(table_name, new_name)
clear_cache!
schema_cache.clear_data_source_cache!(table_name.to_s)
schema_cache.clear_data_source_cache!(new_name.to_s)
execute "ALTER TABLE #{quote_table_name(table_name)} RENAME TO #{quote_table_name(new_name)}"
pk, seq = pk_and_sequence_for(new_name)
if pk
idx = "#{table_name}_pkey"
new_idx = "#{new_name}_pkey"
execute "ALTER INDEX #{quote_table_name(idx)} RENAME TO #{quote_table_name(new_idx)}"
if seq && seq.identifier == "#{table_name}_#{pk}_seq"
new_seq = "#{new_name}_#{pk}_seq"
execute "ALTER TABLE #{seq.quoted} RENAME TO #{quote_table_name(new_seq)}"
end
end
rename_table_indexes(table_name, new_name)
end
🔎 See on GitHub
schema_exists?(name)
Returns true if schema exists.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 63
def schema_exists?(name)
query_value("SELECT COUNT(*) FROM pg_namespace WHERE nspname = #{quote(name)}", "SCHEMA").to_i > 0
end
🔎 See on GitHub
schema_names()
Returns an array of schema names.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 199
def schema_names
query_values(<<~SQL, "SCHEMA")
SELECT nspname
FROM pg_namespace
WHERE nspname !~ '^pg_.*'
AND nspname NOT IN ('information_schema')
ORDER by nspname;
SQL
end
🔎 See on GitHub
schema_search_path()
Returns the active schema search path.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 232
def schema_search_path
@schema_search_path ||= query_value("SHOW search_path", "SCHEMA")
end
🔎 See on GitHub
schema_search_path=(schema_csv)
Sets the schema search path to a string of comma-separated schema names. Names beginning with $ have to be quoted (e.g. $user => '$user'). See: www.postgresql.org/docs/current/static/ddl-schemas.html
This should be not be called manually but set in database.yml.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 224
def schema_search_path=(schema_csv)
if schema_csv
execute("SET search_path TO #{schema_csv}", "SCHEMA")
@schema_search_path = schema_csv
end
end
🔎 See on GitHub
serial_sequence(table, column)
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 255
def serial_sequence(table, column)
query_value("SELECT pg_get_serial_sequence(#{quote(table)}, #{quote(column)})", "SCHEMA")
end
🔎 See on GitHub
validate_check_constraint(table_name, **options)
Validates the given check constraint.
validate_check_constraint :products, name: "price_check"
The options
hash accepts the same keys as add_check_constraint[rdoc-ref:ConnectionAdapters::SchemaStatements#add_check_constraint]
.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 637
def validate_check_constraint(table_name, **options)
chk_name_to_validate = check_constraint_for!(table_name, **options).name
validate_constraint table_name, chk_name_to_validate
end
🔎 See on GitHub
validate_constraint(table_name, constraint_name)
Validates the given constraint.
Validates the constraint named constraint_name
on accounts
.
validate_constraint :accounts, :constraint_name
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 604
def validate_constraint(table_name, constraint_name)
at = create_alter_table table_name
at.validate_constraint constraint_name
execute schema_creation.accept(at)
end
🔎 See on GitHub
validate_foreign_key(from_table, to_table = nil, **options)
Validates the given foreign key.
Validates the foreign key on accounts.branch_id
.
validate_foreign_key :accounts, :branches
Validates the foreign key on accounts.owner_id
.
validate_foreign_key :accounts, column: :owner_id
Validates the foreign key named special_fk_name
on the accounts
table.
validate_foreign_key :accounts, name: :special_fk_name
The options
hash accepts the same keys as SchemaStatements#add_foreign_key.
📝 Source code
# File activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb, line 626
def validate_foreign_key(from_table, to_table = nil, **options)
fk_name_to_validate = foreign_key_for!(from_table, to_table: to_table, **options).name
validate_constraint from_table, fk_name_to_validate
end
🔎 See on GitHub