Mysql Study Notes 001 and mysql Study Notes 001

Mysql Study Notes 001 and mysql Study Notes 001
Mysql is case-insensitive and requires the server to tell him the version number.

Select version ();

Mysql> select version ();
+ ----------- +
| VERSION () |
+ ----------- +
| 5.7.18 |
+ ----------- +
1 row in set (0.09 sec)

Mysql>

Current Time

SELECT CURRENT_TIME ();

Mysql> SELECT CURRENT_TIME ();
+ ---------------- +
| CURRENT_TIME () |
+ ---------------- +
| 13:57:15 |
+ ---------------- +
1 row in set (0.00 sec)

Current date

SELECT CURRENT_DATE ();

Mysql> SELECT CURRENT_DATE ();
+ ---------------- +
| CURRENT_DATE () |
+ ---------------- +
|
+ ---------------- +
1 row in set (0.00 sec)

Mysql>

Another now

Select now ();

Mysql> select now ();
+ --------------------- +
| NOW () |
+ --------------------- +
| 13:57:43 |
+ --------------------- +
1 row in set (0.00 sec)

Mysql>

Simple Calculator

Mysql> select sin (PI ()/4), (4 + 1) * 5;
+ -------------------- + --------- +
| SIN (PI ()/4) | (4 + 1) * 5 |
+ -------------------- + --------- +
| 1, 0.7071067811865475 | 25 |
+ -------------------- + --------- +
1 row in set (0.00 sec)

Mysql>

Who am I

Select user ();

Mysql> select user ();
+ ---------------- +
| USER () |
+ ---------------- +
| Root @ localhost |
+ ---------------- +
1 row in set (0.00 sec)

Mysql>

If I decide not to execute a command in the input process, enter \ c to cancel it.

Mysql> SELECT
-> USER ()
-> \ C
Mysql>

The following table shows the various prompts that you can see and briefly describes the mysql status they represent.

For example, I want to find an 18-year-old girl named Lu in the beautiful girl table, but I have no hands left. I accidentally typed it wrong...

Mysql> SELECT * from beautifulgirls where name = 'lu AND age = 18
'>' \ C
Mysql>

In this way, I can find the pretty girl I want to find (\ happy)