PostgreSQL函数:用以查询某表的详细 包含表字段的注释信息
感谢PostgreSQL论坛阿弟
CREATE OR REPLACE FUNCTION pgsql_type(a_type varchar) RETURNS varchar AS$BODY$DECLARE v_type varchar;BEGIN IF a_type='int8' THEN v_type:='bigint'; ELSIF a_type='int4' THEN v_type:='integer'; ELSIF a_type='int2' THEN v_type:='smallint'; ELSIF a_type='bpchar' THEN v_type:='char'; ELSE v_type:=a_type; END IF; RETURN v_type;END;$BODY$LANGUAGE PLPGSQL;CREATE TYPE "public"."tablestruct" AS ( "fields_key_name" varchar(100), "fields_name" VARCHAR(200), "fields_type" VARCHAR(20), "fields_length" BIGINT, "fields_not_null" VARCHAR(10), "fields_default" VARCHAR(500), "fields_comment" VARCHAR(1000));CREATE OR REPLACE FUNCTION "public"."table_msg" (a_schema_name varchar, a_table_name varchar) RETURNS SETOF "public"."tablestruct" AS$body$DECLARE v_ret tablestruct; v_oid oid; v_sql varchar; v_rec RECORD; v_key varchar;BEGIN SELECT pg_class.oid INTO v_oid FROM pg_class INNER JOIN pg_namespace ON (pg_class.relnamespace = pg_namespace.oid AND lower(pg_namespace.nspname) = a_schema_name) WHERE pg_class.relname=a_table_name; IF NOT FOUND THEN RETURN; END IF; v_sql=' SELECT pg_attribute.attname AS fields_name, pg_attribute.attnum AS fields_index, pgsql_type(pg_type.typname::varchar) AS fields_type, pg_attribute.atttypmod-4 as fields_length, CASE WHEN pg_attribute.attnotnull THEN ''not null'' ELSE '''' END AS fields_not_null, pg_attrdef.adsrc AS fields_default, pg_description.description AS fields_comment FROM pg_attribute INNER JOIN pg_class ON pg_attribute.attrelid = pg_class.oid INNER JOIN pg_type ON pg_attribute.atttypid = pg_type.oid LEFT OUTER JOIN pg_attrdef ON pg_attrdef.adrelid = pg_class.oid AND pg_attrdef.adnum = pg_attribute.attnum LEFT OUTER JOIN pg_description ON pg_description.objoid = pg_class.oid AND pg_description.objsubid = pg_attribute.attnum WHERE pg_attribute.attnum > 0 AND attisdropped <> ''t'' AND pg_class.oid = ' || v_oid || ' ORDER BY pg_attribute.attnum' ; FOR v_rec IN EXECUTE v_sql LOOP v_ret.fields_name=v_rec.fields_name; v_ret.fields_type=v_rec.fields_type; IF v_rec.fields_length > 0 THEN v_ret.fields_length:=v_rec.fields_length; ELSE v_ret.fields_length:=NULL; END IF; v_ret.fields_not_null=v_rec.fields_not_null; v_ret.fields_default=v_rec.fields_default; v_ret.fields_comment=v_rec.fields_comment; SELECT constraint_name INTO v_key FROM information_schema.key_column_usage WHERE table_schema=a_schema_name AND table_name=a_table_name AND column_name=v_rec.fields_name; IF FOUND THEN v_ret.fields_key_name=v_key; ELSE v_ret.fields_key_name=''; END IF; RETURN NEXT v_ret; END LOOP; RETURN ;END;$body$LANGUAGE 'plpgsql' VOLATILE CALLED ON NULL INPUT SECURITY INVOKER;COMMENT ON FUNCTION "public"."table_msg"(a_schema_name varchar, a_table_name varchar)IS '获得表信息';---重载一个函数CREATE OR REPLACE FUNCTION "public"."table_msg" (a_table_name varchar) RETURNS SETOF "public"."tablestruct" AS$body$DECLARE v_ret tablestruct;BEGIN FOR v_ret IN SELECT * FROM table_msg('public',a_table_name) LOOP RETURN NEXT v_ret; END LOOP; RETURN;END;$body$LANGUAGE 'plpgsql' VOLATILE CALLED ON NULL INPUT SECURITY INVOKER;COMMENT ON FUNCTION "public"."table_msg"(a_table_name varchar)IS '获得表信息';例子CREATE TABLE "public"."login_log" ( "auto_bh" BIGSERIAL, "yhm" VARCHAR(20) NOT NULL, "dlsj" TIMESTAMP WITHOUT TIME ZONE DEFAULT date_trunc('second'::text, ('now'::text)::timestamp(6) with time zone) NOT NULL, "dlip" VARCHAR(30) NOT NULL, "dcsj" TIMESTAMP WITHOUT TIME ZONE DEFAULT date_trunc('second'::text, ('now'::text)::timestamp(6) with time zone) NOT NULL, "zc" CHAR(4) NOT NULL, "zxsj" VARCHAR(20) DEFAULT '00:00:00'::character varying, CONSTRAINT "login_log_pkey" PRIMARY KEY("auto_bh", "dlsj")) WITH OIDS;COMMENT ON TABLE "public"."login_log"IS '用户登录日记档';COMMENT ON COLUMN "public"."login_log"."auto_bh"IS '系统编号';COMMENT ON COLUMN "public"."login_log"."yhm"IS '用户名';COMMENT ON COLUMN "public"."login_log"."dlsj"IS '登录时间';COMMENT ON COLUMN "public"."login_log"."dlip"IS '登录IP';COMMENT ON COLUMN "public"."login_log"."dcsj"IS '登出时间';COMMENT ON COLUMN "public"."login_log"."zc"IS '进出';COMMENT ON COLUMN "public"."login_log"."zxsj"IS '在线时间';select * from table_msg('public','login_log');或select * from table_msg('login_log');结果fields_key_name | fields_name | fields_type | fields_length | fields_not_null | fields_default | fields_comment-----------------+-------------+-------------+---------------+-----------------+------------------------------------+---------------- login_log_pkey | auto_bh | bigint | | not null | nextval('public.login_log_auto_bh_seq'::text) | 系统编号 | yhm | varchar | 20 | not null | | 用户名 | dlsj | timestamp | | not null | date_trunc('second'::text, ('now'::text)::timestamp(6) with time zone) | 登录时间 | dlip | varchar | 30 | not null | | 登录IP | dcsj | timestamp | | not null | date_trunc('second'::text, ('now'::text)::timestamp(6) with time zone) | 登出时间 | zc | char | 4 | not null | | 进出 | zxsj | varchar | 20 | | '00:00:00'::character varying | 在线时间(7 rows)