Oracle Database Common Statements

To build a table statement:
CREATE TABLE test1 (ID varchar2 () NOT null primary key);
Add a table field:
ALTER TABLE test1 Add (name VARCHAR2 () default ' null ' NOT NULL);
Add multiple table fields:
ALTER TABLE test1 Add (name VARCHAR2 () default ' null ' not null,age ' null ' for integer default ' not ');
Modify Table Name:
ALTER TABLE table1 Rename to test1;
To delete a table:
1.delete from table name,---is DML, does not take effect when commit is not executed, does not delete table structure, only deletes table contents;
2.drap table name,---the immediate effect cannot be rolled back; execution deletes table structure and dependencies; it does not free up space;
3.truncate table name,---the direct effect can not be rolled back, do not delete the table structure, only delete the table content, will free up space;

To modify a statement:
Update table name set field 1 = ' Value ', field 2 = ' value ' WHERE field = ' value ';

Insert statement:
Insert into table name (Field 1, Field 2, ...) VALUES (' Value ', ' value ', ...) ）；

Or
Insert INTO (select A1,a2,... from table name) VALUES (' Value ', ' value ', ... ）；

Undo operation: Rollback;
Commit action: Commit;

Oracle Database Common Statements