Oracle notes: Tables and fields (3)

Oracle notes: Tables and fields (3) 4. change the field name, size, TYPE, and so on: Change the name: www.2cto.com alter table mytable rename (OLD_FIELD) TO (NEW_FIELD); size and TYPE: alter table mytable modify FIELD_NAME TYPE (LENGTH ); where: when the table is empty, you can change the type and size of the field and change the length from large to small. However, when a record exists, it can only be changed from small to large in some cases, only compatible type. 5. change TABLE name: alter table MYTABLE_OLD rename to MYTABLE_NEW; 6. copy TABLE: create table NEW_TABLE nologigng as select * frm mytable; data is copied at the same time, but its primary key, constraint, trigger, and so on are not copied. 7. alter table mytable move tablespace SPACE_NAME; 8. view the tablespace of the current table: SELECT DEFAULT_TABLESPACE FROM USER_TABLES; 9. view all tables in the current tablespace: SELECT TABLE_NAME, TABLESPACE_NAME FROM USER_TABLES;