postgresql常用查詢

查詢表字段

SELECT
	col.table_schema AS schema_name,
	col.table_name,
	col.column_name,
	col.character_maximum_length,
	col.is_nullable,
	col.numeric_precision,
	col.numeric_scale,
	col.datetime_precision,
	col.ordinal_position,
	b.atttypmod,
	b.attndims,
	col.data_type AS col_type,
	et.typelem,
	et.typlen,
	et.typtype,
	nbt.nspname AS elem_schema,
	bt.typname AS elem_name,
	b.atttypid,
	col.udt_schema,
	col.udt_name,
	col.domain_catalog,
	col.domain_schema,
	col.domain_name,
	col_description ( c.oid, col.ordinal_position ) AS COMMENT,
	col.column_default AS col_default,
	b.attacl,
	colnsp.nspname AS collation_schema_name,
	coll.collname,
	c.relkind,
	b.attfdwoptions AS foreign_options 
FROM
	information_schema.COLUMNS AS col
	LEFT JOIN pg_namespace ns ON ns.nspname = col.table_schema
	LEFT JOIN pg_class c ON col.table_name = c.relname 
	AND c.relnamespace = ns.oid
	LEFT JOIN pg_attrdef a ON c.oid = a.adrelid 
	AND col.ordinal_position = a.adnum
	LEFT JOIN pg_attribute b ON b.attrelid = c.oid 
	AND b.attname = col.column_name
	LEFT JOIN pg_type et ON et.oid = b.atttypid
	LEFT JOIN pg_collation coll ON coll.oid = b.attcollation
	LEFT JOIN pg_namespace colnsp ON coll.collnamespace = colnsp.oid
	LEFT JOIN pg_type bt ON et.typelem = bt.oid
	LEFT JOIN pg_namespace nbt ON bt.typnamespace = nbt.oid 
WHERE
	col.table_schema = 'public' 
	AND col.table_name = 'tableName' 
ORDER BY
	col.table_schema,
	col.table_name,
	col.ordinal_position

tableName:表名

base64

select convert_from(decode(encode('123ds大鍋','base64'),'base64'),'utf-8')