Extraire la structure d'une base de données

select distinct schemaname from pg_catalog.pg_statio_all_tables order by schemaname;

select schemaname, relname as tablename, description

       from pg_catalog.pg_statio_all_tables st

        join pg_catalog.pg_description on (relid = objoid and objsubid = 0)

        where schemaname in 

        ('public', 'schema1', 'schema2')

        order by schemaname, relname;

with req as 

        (SELECT DISTINCT on ( schemaname, tablename, field) schemaname, pg_tables.tablename 

           ,attnum  

           ,pg_attribute.attname AS field

            ,format_type(pg_attribute.atttypid,NULL) AS "type"

            ,pg_constraint.conname AS "key"

             ,CASE pg_attribute.attnotnull

            WHEN FALSE THEN null

           ELSE 1

         END AS "notnull"

         ,(SELECT col_description(pg_attribute.attrelid,pg_attribute.attnum)) AS COMMENT

          ,pc2.conname AS ckey

         ,(SELECT pg_attrdef.adsrc

          FROM pg_attrdef

          WHERE pg_attrdef.adrelid = pg_class.oid

          AND   pg_attrdef.adnum = pg_attribute.attnum) AS def

        FROM pg_tables,

       pg_class

       JOIN pg_attribute

       ON pg_class.oid = pg_attribute.attrelid

       AND pg_attribute.attnum > 0

       LEFT JOIN pg_constraint

           ON pg_constraint.contype = 'p'::"char"

           AND pg_constraint.conrelid = pg_class.oid

           AND (pg_attribute.attnum = ANY (pg_constraint.conkey))

        LEFT JOIN pg_constraint AS pc2

           ON pc2.contype = 'f'::"char"

           AND pc2.conrelid = pg_class.oid

           AND (pg_attribute.attnum = ANY (pc2.conkey))

        WHERE pg_class.relname = pg_tables.tablename

        AND   pg_attribute.atttypid <> 0::OID

        and schemaname in 

        ('public', 'schema1', 'schema2')

       ORDER BY schemaname, tablename, field ASC)

        select * from req order by schemaname, tablename, attnum;