Database (2)

Dml

A.insert (insert)
Syntax: INSERT into table name (column name ... Values (Value ...) ）
Eg:insert into student (id,name,addr,) values (11,, ' Zhang San ', ' City Houses ');
Note: 1) The column an array and the number of values to be consistent
2) Primary key columns cannot be duplicated
3) Non-empty columns cannot insert null values

1 --User Table2 INSERT  intoQqusers (Qqid,password,lastlogtime,online, Level)VALUES(54789625,'add512#&','2013-02-16 17:01:35',2,1);3 INSERT  intoQqusersVALUES(88662753,'admin0219','2013-02-19 21:08:50',0,5);4 INSERT  intoQqusersVALUES(8855678,'guest0221','2013-02-21 16:28:20',1,6);

Insert Representation Example

B.delete (delete)
Syntax: Delete from table name where condition
Eg:delete from student where id=1;
Note: If there is no where condition, then delete from table name; Delete all records of table

1 -- Delete 2 DELETE  from WHERE EMPNO=;

Delete Information Example

C.update (Modify update)
Syntax: Update table name set column name 1= value 1, column name 2= value 2 ... where condition

1 --  2UPDATESET ename='YY'WHERE EMPNO=.

Modifying a presentation example

Database (2)