oracle查询用户下表总数、表字段总数、表记录总数

--查询用户下的表数量
SELECT COUNT(1) FROM USER_TABLES;

--查询用户下的表的字段数量
SELECT COUNT(1)
FROM USER_COL_COMMENTS C
WHERE EXISTS
(SELECT 1 FROM USER_TABLES T WHERE T.TABLE_NAME = C.TABLE_NAME);

--查询表记录数量
SELECT T.TABLE_NAME, T.NUM_ROWS, T.BLOCKS, T.EMPTY_BLOCKS
FROM USER_TABLES T;

--查询表备注
SELECT TABLE_NAME, TABLE_TYPE, COMMENTS
FROM USER_TAB_COMMENTS
WHERE COMMENTS LIKE '%字典%'

----查询表所占空间
analyze table T_DATA compute statistics;

SELECT NUM_ROWS , AVG_ROW_LEN
FROM USER_TABLES
WHERE TABLE_NAME = 'T_DATA';

SELECT SEGMENT_NAME, SUM(BYTES) / 1024 / 1024
FROM USER_EXTENTS
GROUP BY SEGMENT_NAME;