Strange loop behavior in mysql cause missing values - mysql

Question

Hope you are fine. I usually have to create databases for my studies and to make tests and homework,
Main question
I coded a for loop for a foreign key and apparently it gave a group of each 8 rows followed by 8 rows with null value in a sort of cycle; despite the fact I ran the procedure several times.
Is just me ?
Code
CREATE DATABASE Taller2;
CREATE TABLE numeros (
numero INT NOT NULL,
CONSTRAINT XPKnumeros
PRIMARY KEY CLUSTERED (numero));
USE Taller2;
CREATE OR REPLACE VIEW generator_8
AS SELECT 0 n UNION ALL SELECT 1 UNION ALL SELECT 2 UNION ALL
SELECT 3 UNION ALL SELECT 4 UNION ALL SELECT 5 UNION ALL
SELECT 6 UNION ALL SELECT 7 UNION ALL SELECT 8 ;
USE Taller2;
CREATE OR REPLACE VIEW generator_64
AS SELECT ( hi.n * 16 + lo.n ) AS n
FROM generator_8 lo
, generator_8 hi;
USE Taller2;
INSERT INTO numeros(numero)
SELECT n FROM generator_64 WHERE n <= 50;
-- It should give me a list of 1 to 50
select * from taller2.numeros
Then I coded this two tables:
USE Taller2;
CREATE TABLE Taller2.T1 (
ID INT NOT NULL AUTO_INCREMENT
,Nombre VARCHAR(30) NULL
,dia DATE NOT NULL
,numerox FLOAT DEFAULT (RAND()*RAND()),
PRIMARY KEY (ID)
);
CREATE TABLE Taller2.T2 (
ID INT NOT NULL AUTO_INCREMENT
,IDT1 INT NULL
,Nombre VARCHAR(30) NULL
,dia DATE NOT NULL
,numerox FLOAT DEFAULT (RAND()*RAND()),
PRIMARY KEY (ID),
FOREIGN KEY (IDT1) REFERENCES Taller2.T1(ID)
);
Then these two procedures using dynamic sql:
USE Taller2;
DELIMITER //
CREATE PROCEDURE InsertData(IN Tabla VARCHAR(3))
BEGIN
DECLARE i INT DEFAULT 1;
SET #cod_sql = CONCAT('INSERT INTO Taller2.',Tabla,' (dia,Nombre) VALUES (?,CONCAT("Animal",?));');
WHILE (i <= 50) DO
PREPARE s1 from #cod_sql;
SET #parametro1 = DATE_ADD(curdate(), INTERVAL FLOOR(RAND()*(10-0)+0) DAY);
SET #parametro2 = CONVERT(FLOOR(RAND()*(10-0) + 0),CHAR);
EXECUTE s1 USING #parametro1,#parametro2;
SET i = i+1;
END WHILE;
END;
//
DELIMITER ;
-- DROP PROCEDURE InsertData;
-- Inserting Data
CALL InsertData('T1');
CALL InsertData('T2');
CALL Insertfk();
-- Showing the data
SELECT * FROM taller2.t1;
SELECT * FROM taller2.t2;
DELIMITER //
CREATE PROCEDURE Insertfk()
BEGIN
DECLARE i INT DEFAULT 1;
WHILE (i <= 50) DO
UPDATE taller2.t2 -- I know this is too raw but I was in a hurry
SET IDT1 = ( select numero from taller2.numeros WHERE numero = i)
WHERE ID = i;
SET i = i+1;
END WHILE;
END;
//
DELIMITER ;
CALL InsertData('T1');
CALL InsertData('T2');
CALL Insertfk();
SELECT * FROM taller2.t1;
SELECT * FROM taller2.t2;
And the following lines contained nulls Which I manually fixed because they werent too many
UPDATE `taller2`.`t2` SET `IDT1` = '9' WHERE (`ID` = '9');
UPDATE `taller2`.`t2` SET `IDT1` = '10' WHERE (`ID` = '10');
UPDATE `taller2`.`t2` SET `IDT1` = '11' WHERE (`ID` = '11');
UPDATE `taller2`.`t2` SET `IDT1` = '12' WHERE (`ID` = '12');
UPDATE `taller2`.`t2` SET `IDT1` = '13' WHERE (`ID` = '13');
UPDATE `taller2`.`t2` SET `IDT1` = '14' WHERE (`ID` = '14');
UPDATE `taller2`.`t2` SET `IDT1` = '15' WHERE (`ID` = '15');
UPDATE `taller2`.`t2` SET `IDT1` = '25' WHERE (`ID` = '25');
UPDATE `taller2`.`t2` SET `IDT1` = '26' WHERE (`ID` = '26');
UPDATE `taller2`.`t2` SET `IDT1` = '28' WHERE (`ID` = '28');
UPDATE `taller2`.`t2` SET `IDT1` = '29' WHERE (`ID` = '29');
UPDATE `taller2`.`t2` SET `IDT1` = '30' WHERE (`ID` = '30');
UPDATE `taller2`.`t2` SET `IDT1` = '31' WHERE (`ID` = '31');
UPDATE `taller2`.`t2` SET `IDT1` = '41' WHERE (`ID` = '41');
UPDATE `taller2`.`t2` SET `IDT1` = '42' WHERE (`ID` = '42');
UPDATE `taller2`.`t2` SET `IDT1` = '43' WHERE (`ID` = '43');
UPDATE `taller2`.`t2` SET `IDT1` = '44' WHERE (`ID` = '44');
UPDATE `taller2`.`t2` SET `IDT1` = '45' WHERE (`ID` = '45');
UPDATE `taller2`.`t2` SET `IDT1` = '46' WHERE (`ID` = '46');
UPDATE `taller2`.`t2` SET `IDT1` = '47' WHERE (`ID` = '47');
Any idea why?
I have MySQL 8.0 and
this is the processor: Intel(R) Core(TM) i7-6600U CPU # 2.60GHz 2.81 GHz
This is the Ram: 8.00 GB (7.88 GB usable)
Thanks,

Answer 1

I think in your trailer table column name is numerox
but in ur select query in procedure it ' numero