PostgreSQL的表一般都是建立在public这个schema下的,假如现在有个数据表t_student
,可以用以下几种方式来查询表结构和索引信息。
在cmd界面使用psql连接db后,输入\d加上表名即可:
1 | \d t_student |
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 | select col.table_schema, col.table_name, col.ordinal_position, col.column_name, col.data_type, col.character_maximum_length, col.numeric_precision, col.numeric_scale, col.is_nullable, col.column_default, des.description from information_schema.columns col left join pg_description des on col.table_name::regclass = des.objoid and col.ordinal_position = des.objsubid where table_schema = 'public' and table_name = 't_student' order by ordinal_position; |
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或者简单点:
1 2 | select * from information_schema.columns where table_schema='public' and table_name='t_student'; |
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 | select A.SCHEMANAME, A.TABLENAME, A.INDEXNAME, A.TABLESPACE, A.INDEXDEF, B.AMNAME, C.INDEXRELID, C.INDNATTS, C.INDISUNIQUE, C.INDISPRIMARY, C.INDISCLUSTERED, D.DESCRIPTION from PG_AM B left join PG_CLASS F on B.OID = F.RELAM left join PG_STAT_ALL_INDEXES E on F.OID = E.INDEXRELID left join PG_INDEX C on E.INDEXRELID = C.INDEXRELID left outer join PG_DESCRIPTION D on C.INDEXRELID = D.OBJOID, PG_INDEXES A where A.SCHEMANAME = E.SCHEMANAME and A.TABLENAME = E.RELNAME and A.INDEXNAME = E.INDEXRELNAME and E.SCHEMANAME = 'public' and E.RELNAME = 't_student'; |
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1 2 3 4 5 6 7 8 9 10 11 12 | select n.nspname, relname from pg_class c, pg_namespace n where c.relnamespace = n.oid and nspname = 'public' and relkind = 'r' order by relname; |
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对于上述的sql语句只需要修改要查询的table name,可以根据需要自行修改想要查询的column。如果是通过DBeaver来连接数据库,还可以直接在当前的数据库实例下打开schema里的public选项,接着选中table,选中你想查看的表,可以很直观地看到该表的各种信息:column、index等等。
警告
本文最后更新于 November 19, 2018,文中内容可能已过时,请谨慎使用。