MySQL

MySQL Tutorial is an fast way to learn mysql language with examples for beginners developers.
On this course you can learn about MySQL language using this mysql tutorial based on simple and complex examples.
MySQL language is a widely used relational database management based on SQL language.

The main sections of MySQL language are:

• Database
• Data Types
• Clauses
• Insert
• Update
• Delete
• Select
• Flow Control Statements
• Functions and Operators
• Table
• View
• Temporary Table
• Triggers
• Procedure
• Function
• Indexes
• Transactions

Start learn mysql using the basic commands like:

• How to Create table
• How to Create procedure
• How to Create or replace function
• How to Create trigger
• How to add primary key in existing table
• How to add foreign key to existing table
• How to add a column to an existing table
• How to add an index to table

MySQL Flow Control Statements

The MySQL Flow Control Statements are:

• CASE
• IF
• ITERATE
• LEAVE
• LOOP
• REPEAT
• RETURN
• WHILE

MySQL While

MySQL While syntax and example.
The WHILE statement is repeated as long as the condition expression is true.

MySQL While syntax

[ begin_label: ] WHILE condition DO
mysql_code
END WHILE [ end_label ]

While example

CREATE PROCEDURE while_proc(x int)
BEGIN
DECLARE i INT DEFAULT 0;
DECLARE y INT;
SET y = x;
	WHILE y > 0 DO
		IF i=0 THEN 
			SET i = x+1;
		ELSE
			SET i = i+1;
		END IF;	
		SET y = y - 1;
	END WHILE;
	SELECT i;
END;

CALL while_proc(5);

Output

PROCEDURE WHILE_PROC compiled
i
10

MySQL Return

MySQL Return syntax and example.
The RETURN statement terminates execution of a stored function and returns the value expr to the function caller.

Return example

CREATE FUNCTION return_value(x INT)
RETURNS TEXT
BEGIN
	IF x=1 THEN
		RETURN 'OK';
	ELSE
		RETURN 'NOK';
	END IF;
END;

SELECT return_value(1);

Output

FUNCTION RETURN_VALUE compiled
OK

MySQL Repeat

MySQL Repeat syntax and example.
The statement list within a REPEAT statement is repeated until the search_condition expression is true.

MySQL Repeat syntax

[ begin_label: ] REPEAT
statement_list
UNTIL search_condition
END REPEAT [ end_label ]

Repeat example

CREATE PROCEDURE repeat_proc(x INT)
BEGIN
DECLARE total INT;
SET total = 0;
	REPEAT
		SET total = total + 1;
		UNTIL total > x 
	END REPEAT;
  SELECT total;
END;

CALL repeat_proc(10);

Output

PROCEDURE REPEAT_PROC compiled
total
11