oracle 查詢表名、字段名、添加注釋

--查詢所有表名
SELECT T.TABLE_NAME FROM USER_TABLES T;

--查詢所有字段名
SELECT T.COLUMN_NAME FROM USER_COL_COMMENTS T;

--查詢指定表字段名和注釋
SELECT T.COLUMN_NAME ,T.COMMENTS FROM USER_COL_COMMENTS T WHERE T.TABLE_NAME = 'T_THREE_KILLED';

--查詢表的數據條數、表名、中文表名
SELECT A.NUM_ROWS, A.TABLE_NAME, B.COMMENTS FROM USER_TABLES A, USER_TAB_COMMENTS B;
WHERE A.TABLE_NAME = B.TABLE_NAME ORDER BY TABLE_NAME;

--給表添加注釋
COMMENT ON TABLE T_THREE_KILLED IS '三國殺人物表';

--給列添加注釋
COMMENT ON COLUMN T_THREE_KILLED.C_SKILL IS '技能';

--給列起別名 AS 和雙引號可以去掉
SELECT T.C_NAME AS "姓名",T.C_SKILL AS "技能" FROM T_THREE_KILLED T;

--去重
SELECT DISTINCT T.C_AGE FROM T_THREE_KILLED t;