select(select relname||'--'||(select description from pg_description where objoid=oid and objsubid=0) as comment from pg_class where oid=a.attrelid) as table_name,a.attname as column_name,format_type(a.atttypid,a.atttypmod) as data_type,(case when atttypmod-4>0 then atttypmod-4 else 0 end)data_length,(case when (select count(*) from pg_constraint where conrelid = a.attrelid and conkey[1]=attnum and contype='p')>0 then 'Y' else 'N' end) as 主键约束,(case when (select count(*) from pg_constraint where conrelid = a.attrelid and conkey[1]=attnum and contype='u')>0 then 'Y' else 'N' end) as 唯一约束,(case when (select count(*) from pg_constraint where conrelid = a.attrelid and conkey[1]=attnum and contype='f')>0 then 'Y' else 'N' end) as 外键约束,(case when a.attnotnull=true then 'Y' else 'N' end) as nullable,col_description(a.attrelid,a.attnum) as commentfrom pg_attribute awhere attstattarget=-1 and attrelid in (select oid from pg_class where relname in(select relname from pg_class where relkind ='r' and relname like 'tbl_%'))order by table_name,a.attnum;