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mysql> create table mytesttable
-> (
-> rollno int,
-> firstname varchar(50),
-> lastname varchar(50)
-> );
Query OK, 0 rows affected (0.25 sec)
or
create table mytesttable(
rollno int primary key auto_increment,
firstname varchar(50) not null,
lastname varchar(50) not null,
CreatedDTTM DATETIME DEFAULT NOW()
);
SELECT CONCAT(firstname, ' ', lastname) as fullname FROM mytesttable;
-- salary numeric(10, 2) not null,
-- IsDeleted bit not null default 0,
-- 8 digits for integer part and 2 digits for fraction part
-- varchar cost less than char
mysql> SHOW COLUMNS FROM mytesttable;
+-----------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+-----------+-------------+------+-----+---------+-------+
| rollno | int | YES | | NULL | |
| firstname | varchar(50) | YES | | NULL | |
| lastname | varchar(50) | YES | | NULL | |
+-----------+-------------+------+-----+---------+-------+
3 rows in set (0.06 sec)
mysql> select rollno, firstname, lastname from mytesttable;
Empty set (0.00 sec)
-- select distinct lastname from mytesttable;
-- select sum(rollno) as s from mytesttable;
-- sum(), min(), max(), avg(), count()
mysql> insert into mytesttable(rollno, firstname, lastname) values(1, 'Eric', 'Lu');
Query OK, 1 row affected (0.03 sec)
-- insert into mytesttable(rollno, firstname, lastname, CreatedDTTM) values(1, 'Eric', 'Lu', now());
mysql> select firstname from mytestdb.mytesttable;
+-----------+
| firstname |
+-----------+
| Eric |
+-----------+
1 row in set (0.01 sec)
-- select * from mytestdb.mytesttable order by rollno desc;
mysql> select firstname from mytestdb.mytesttable where lastname like 'hsu';
Empty set (0.01 sec)
mysql> select firstname from mytestdb.mytesttable where lastname like 'u';
Empty set (0.00 sec)
mysql> select firstname from mytestdb.mytesttable where lastname like 'Lu';
+-----------+
| firstname |
+-----------+
| Eric |
+-----------+
1 row in set (0.00 sec)
mysql> insert into mytesttable(rollno, firstname, lastname) values(2, 'Shvara', 'Lunski');
Query OK, 1 row affected (0.04 sec)
mysql> insert into mytesttable(rollno, firstname, lastname) values(3, 'Lunski', 'Henry');
Query OK, 1 row affected (0.01 sec)
|
