删除表时，表上的约束没跟着被删除？
--第一步：创建表，及相应的主键约束pk_test_idSQL> create table test(id number constraint pk_test_id primary key);Table created.--第二步：此时总共有9个约束SQL> select constraint_name from user_constraints;CONSTRAINT_NAME------------------------------BIN$vL7ij8sVLTjgQAB/AQAPeg==$0PK_TEST_IDBIN$vL7ij8sYLTjgQAB/AQAPeg==$0BIN$uvy0dxvyoYvgQAB/AQAMpQ==$0BIN$uvy0dxwAoYvgQAB/AQAMpQ==$0BIN$uvy0dxvsoYvgQAB/AQAMpQ==$0BIN$uvy0dxvvoYvgQAB/AQAMpQ==$0BIN$uvy0dxv6oYvgQAB/AQAMpQ==$0BIN$uvy0dxv9oYvgQAB/AQAMpQ==$09 rows selected.--第三步：删除表,按理说相应的约束应该被干掉了SQL> drop table test;Table dropped.--第四步：此时还有9个约束，只是把约束的名称改了下，难道相应的约束没被干掉？SQL> select constraint_name from user_constraints;CONSTRAINT_NAME------------------------------BIN$vL7ij8sVLTjgQAB/AQAPeg==$0BIN$vL7ij8sYLTjgQAB/AQAPeg==$0BIN$vL7ij8sbLTjgQAB/AQAPeg==$0BIN$uvy0dxvyoYvgQAB/AQAMpQ==$0BIN$uvy0dxwAoYvgQAB/AQAMpQ==$0BIN$uvy0dxvsoYvgQAB/AQAMpQ==$0BIN$uvy0dxvvoYvgQAB/AQAMpQ==$0BIN$uvy0dxv6oYvgQAB/AQAMpQ==$0BIN$uvy0dxv9oYvgQAB/AQAMpQ==$09 rows selected.
SQL> create table test(id number constraint pk_test_id primary key); Table createdSQL> select table_name from user_tables; TABLE_NAME------------------------------TESTSQL> select table_name,constraint_name from user_constraints; TABLE_NAME CONSTRAINT_NAME------------------------------ ------------------------------TEST PK_TEST_IDSQL> drop table test; Table droppedSQL> select table_name from user_tables; --BIN$VnncqINTRy+7ruGTE76IlQ==$0为删除后的表名 TABLE_NAME------------------------------BIN$VnncqINTRy+7ruGTE76IlQ==$0 SQL> select table_name,constraint_name from user_constraints; --table_name跟user_table的表名相同，可以关联上 TABLE_NAME CONSTRAINT_NAME------------------------------ ------------------------------BIN$VnncqINTRy+7ruGTE76IlQ==$0 BIN$nIZCU2gMRrujmIOafsDtBg==$0SQL> flashback recyclebin; --清空回收站 DoneSQL> select table_name from user_tables; TABLE_NAME------------------------------SQL> select table_name,constraint_name from user_constraints; TABLE_NAME CONSTRAINT_NAME------------------------------ ------------------------------
