Variables and control flow in MySQL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a variable named 'counter' with initial value 0.

MySQL

DECLARE counter [1];

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AINT DEFAULT 0

BVARCHAR(10)

CDATE

DTEXT

Attempts:

3 left

💡 Hint

Common Mistakes

Using VARCHAR for a number variable.

Not setting an initial value.

In MySQL, to declare a variable with an initial integer value, use INT DEFAULT 0.

2fill in blank

medium

Complete the code to set the variable 'counter' to 5.

MySQL

SET [1] = 5;

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A@counter

Bcounter

C$counter

D#counter

Attempts:

3 left

💡 Hint

Common Mistakes

Using @ prefix which is for user-defined session variables.

Using $ or # which are not valid prefixes.

In MySQL stored programs, local variables are referenced by their name without any prefix.

3fill in blank

hard

Fix the error in the IF statement to check if 'counter' is less than 10.

MySQL

IF counter [1] 10 THEN
  SET counter = counter + 1;
END IF;

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A!=

B=

C==

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using == which is invalid in MySQL.

Using = which is assignment, not comparison.

In MySQL, the less than operator is < to compare values.

4fill in blank

hard

Fill both blanks to create a WHILE loop that runs while 'counter' is less than 5.

MySQL

WHILE counter [1] 5 DO
  SET counter = counter [2] 1;
END WHILE;

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A<

B+

C-

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using > which reverses the loop condition.

Using - which decreases counter causing infinite loop.

The loop continues while counter is less than 5, and increments counter by 1 each time.

5fill in blank

hard

Fill all three blanks to declare a variable 'total', set it to 0, and increment it by 'value' inside a loop.

MySQL

DECLARE [1] INT DEFAULT 0;
SET [2] = 0;
SET total = total [3] value;

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Atotal

C+

D-

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names in declaration and assignment.

Using - which subtracts instead of adds.

Declare 'total' as INT with default 0, initialize it to 0, then add 'value' to 'total'.