Let us first create a table. The query to create a table is as follows
mysql> create table selectAllDemo - > ( - > Name varchar(100), - > Age int - > ); Query OK, 0 rows affected (1.90 sec)
Insert some records in the table using insert command.
The query is as follows
mysql> insert into selectAllDemo values('John',25); Query OK, 1 row affected (0.99 sec) mysql> insert into selectAllDemo values('Carol',26); Query OK, 1 row affected (0.42 sec) mysql> insert into selectAllDemo values('Bob',30); Query OK, 1 row affected (1.57 sec) mysql> insert into selectAllDemo values('Sam',35); Query OK, 1 row affected (0.26 sec)
Display all records from the table using select statement.
The query is as follows
mysql> select *from selectAllDemo;
The following is the output
+-------+------+ | Name | Age | +-------+------+ | John | 25 | | Carol | 26 | | Bob | 30 | | Sam | 35 | +-------+------+ 4 rows in set (0.16 sec)
Here is the query to select only the ID column as NULL
mysql> select NULL AS Id,tbl.Name,tbl.Age from selectAllDemo tbl where Age=35;
The following is the output
+------+------+------+ | Id | Name | Age | +------+------+------+ | NULL | Sam | 35 | +------+------+------+ 1 row in set (0.07 sec)