| Courtesy of Andy Hassall |
conn sys@pdbdev as sysdba
show parameter db_block_size
conn uwclass/uwclass
SQL> @?/rdbms/admin/utlchn1.sql
CREATE TABLE t (
col1 VARCHAR2(4000),
col2 VARCHAR2(4000));
INSERT INTO t VALUES ('x', '1');
INSERT INTO t VALUES ('xx', '2');
INSERT INTO t
(col1, col2)
VALUES
(LPAD('x',4096,'x'), LPAD('x',4096,'x'));
INSERT INTO t VALUES ('xxxx', '4');
INSERT INTO t VALUES ('xxxxx', '5');
COMMIT;
ANALYZE TABLE t LIST
CHAINED ROWS INTO chained_rows;
set linesize 121
col table_name format a15
col head_rowid format a20
SELECT sys_op_rpb(rowid), table_name, head_rowid, analyze_timestamp
FROM chained_rows;
SELECT rowid, dbms_rowid.rowid_block_number(rowid) BN, sys_op_rpb(rowid), length(col1), length(col2)
FROM t;
SELECT table_name, chain_cnt
FROM user_tables
WHERE chain_cnt <> 0
ORDER BY 1;
ANALYZE TABLE t COMPUTE STATISTICS;
SELECT table_name, chain_cnt
FROM user_tables
WHERE chain_cnt <> 0
ORDER BY 1; |