What are the circular statements of MySQL

MySQL What are the loop statements of

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mysql There are three common ways of cycling ：while、repeat and loop loop . There is another kind. goto, It is not recommended to use .

1.while loop

--  Set up mysql The separator is //, That means , When it comes to the next one // when , Overall execution SQL sentence 
DELIMITER //

DROP PROCEDURE if EXISTS ‘test’;    #  If there is test Stored procedures are deleted CREATE procedure test() #  Create a parameterless stored procedure , The name is testBEGIN
DECLARE i INT;  #  Declare variables SET i = 0;  #  Variable assignment WHILE i#  Conditions for ending the cycle :  When i Greater than 5 Jump out when while loop 
INSERT INTO test VALUES(i+11,'test','20');  #  Go to test Table add data SET i = i+1;    #  Cycle time ,i Add 1END WHILE;  #  end while loop SELECT * FROM test; #  see test Table data END
//  #  End definition statement CALL test();    #  Calling stored procedure DELIMITER ; #  Reset the separator to ;

2.repeat loop

DELIMITER //
DROP PROCEDURE IF EXISTS test;
CREATE PROCEDURE test()
BEGIN
 DECLARE i INT;
 SET i = 0;
 REPEAT
   INSERT INTO test VALUES(i+11,'test','20');           #  Go to test Table add data    SET i = i + 1;                                  #  Cycle time ,i Add one  UNTIL i > 10 END REPEAT;                           #  Conditions for ending the cycle :  When i Greater than 10 Jump out when repeat loop  SELECT * FROM test;
END
//
CALL test();
DELIMITER ;

3.loop loop

DELIMITER //
DROP PROCEDURE IF EXISTS test;
CREATE PROCEDURE test()
BEGIN
 DECLARE i INT;
 SET i = 0;
   lp : LOOP                                   # lp Is the body name of the loop , Feel free to  loop Keyword        INSERT INTO test VALUES(i+11,'test','20');   #  Go to test Table add data        SET i = i + 1;                          #  Cycle time ,i Add one        IF i > 10 THEN                       #  Conditions for ending the cycle :  When i Greater than 10 Jump out when loop loop                    LEAVE lp;
           END IF;
   END LOOP;
   SELECT * FROM test;
END
//
CALL test();
DELIMITER ;

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