CREATE PROCEDURE syntax in SQL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to start creating a stored procedure named 'GetAllUsers'.

SQL

CREATE [1] GetAllUsers AS BEGIN SELECT * FROM Users; END;

Drag options to blanks, or click blank then click option'

APROCEDURE

BVIEW

CTRIGGER

DFUNCTION

Attempts:

3 left

💡 Hint

Common Mistakes

Using FUNCTION instead of PROCEDURE

Using VIEW or TRIGGER keywords incorrectly

The keyword PROCEDURE is used to create a stored procedure in SQL.

2fill in blank

medium

Complete the code to define a parameter named 'UserId' of type INT for the procedure.

SQL

CREATE PROCEDURE GetUserById ([1] INT) AS BEGIN SELECT * FROM Users WHERE Id = @UserId; END;

Drag options to blanks, or click blank then click option'

A#UserId

BUserId

C@UserId

D$UserId

Attempts:

3 left

💡 Hint

Common Mistakes

Omitting the '@' symbol before parameter names

Using '#' or '$' which are not standard for parameters

In many SQL dialects, procedure parameters start with '@' to denote variables.

3fill in blank

hard

Fix the error in the procedure declaration by choosing the correct keyword to end the procedure.

SQL

CREATE PROCEDURE DeleteUser (@UserId INT) AS BEGIN DELETE FROM Users WHERE Id = @UserId; [1] END;

Drag options to blanks, or click blank then click option'

AEND

BSTOP

CFINISH

DEXIT

Attempts:

3 left

💡 Hint

Common Mistakes

Using STOP or FINISH which are not valid SQL keywords

Using EXIT which is for control flow, not block ending

The END keyword is used to close the BEGIN block in SQL procedures.

4fill in blank

hard

Fill both blanks to create a procedure that updates a user's email by their ID.

SQL

CREATE PROCEDURE UpdateEmail ([1] INT, [2] VARCHAR(100)) AS BEGIN UPDATE Users SET Email = @Email WHERE Id = @UserId; END;

Drag options to blanks, or click blank then click option'

A@UserId

B@Email

CUserId

DEmail

Attempts:

3 left

💡 Hint

Common Mistakes

Omitting '@' in parameter names

Using parameter names that don't match the procedure body

Parameters must be prefixed with '@' and match the names used inside the procedure.

5fill in blank

hard

Fill all three blanks to create a procedure that inserts a new user with name and age.

SQL

CREATE PROCEDURE AddUser ([1] VARCHAR(50), [2] INT) AS BEGIN INSERT INTO Users (Name, Age) VALUES ([3], @Age); END;

Drag options to blanks, or click blank then click option'

A@Name

B@Age

DName

Attempts:

3 left

💡 Hint

Common Mistakes

Using column names instead of parameter names in VALUES

Not prefixing parameters with '@'

Parameters must be prefixed with '@' and used consistently inside the procedure.

Practice

1. What is the main purpose of the CREATE PROCEDURE statement in SQL?

easy

A. To display data from a table

B. To delete data from a table

C. To create a new database

D. To save a set of SQL commands that can be run later

Solution

1. Step 1: Understand the purpose of CREATE PROCEDURE

   The CREATE PROCEDURE statement is used to save a group of SQL commands as a procedure that can be executed later.

2. Step 2: Compare options with the purpose

   Options B, C, and D describe other SQL commands, not the purpose of CREATE PROCEDURE.

3. Final Answer:

   To save a set of SQL commands that can be run later -> Option D

4. Quick Check:

   CREATE PROCEDURE saves commands = A [OK]

Hint: Remember: procedures store commands to run later [OK]

Common Mistakes:

• Confusing CREATE PROCEDURE with CREATE TABLE
• Thinking it runs commands immediately
• Mixing it up with SELECT statement

2. Which of the following is the correct basic syntax to create a procedure named GetUsers without parameters?

easy

A. CREATE PROCEDURE GetUsers AS SELECT * FROM Users;

B. CREATE PROCEDURE GetUsers BEGIN SELECT * FROM Users; END;

C. CREATE PROCEDURE GetUsers() BEGIN SELECT * FROM Users; END;

D. CREATE PROCEDURE GetUsers SELECT * FROM Users;

Solution

1. Step 1: Recall standard procedure syntax

   The correct syntax includes parentheses for parameters (empty if none), and a BEGIN...END block to enclose statements.

2. Step 2: Check each option

   CREATE PROCEDURE GetUsers() BEGIN SELECT * FROM Users; END; correctly uses CREATE PROCEDURE GetUsers() BEGIN SELECT * FROM Users; END;. Options A, C, and D miss parentheses or BEGIN...END or have syntax errors.

3. Final Answer:

   CREATE PROCEDURE GetUsers() BEGIN SELECT * FROM Users; END; -> Option C

4. Quick Check:

   Procedure syntax needs () and BEGIN...END = B [OK]

Hint: Always use () and BEGIN...END in procedure syntax [OK]

Common Mistakes:

• Omitting parentheses after procedure name
• Not using BEGIN and END to wrap statements
• Missing semicolon inside procedure

3. Given the procedure below, what will be the output when calling CALL GetUserCount();?

CREATE PROCEDURE GetUserCount()
BEGIN
  SELECT COUNT(*) AS TotalUsers FROM Users;
END;

medium

A. No output because procedure does not return anything

B. The total number of rows in the Users table

C. Syntax error because of missing parameters

D. An error because SELECT cannot be used in procedures

Solution

1. Step 1: Understand what the procedure does

   The procedure runs a SELECT COUNT(*) query on the Users table and returns the count as TotalUsers.

2. Step 2: Analyze the CALL statement output

   Calling CALL GetUserCount(); executes the procedure and returns the count of rows in Users table as a result set.

3. Final Answer:

   The total number of rows in the Users table -> Option B

4. Quick Check:

   CALL runs procedure and returns SELECT result = C [OK]

Hint: CALL runs procedure and returns SELECT results [OK]

Common Mistakes:

• Thinking procedures cannot return SELECT results
• Assuming parameters are always required
• Confusing procedure call with function call

4. Identify the error in the following procedure definition:

CREATE PROCEDURE AddUser(
  IN username VARCHAR(50),
  IN email VARCHAR(100)
)
INSERT INTO Users (Username, Email) VALUES (username, email);
END;

medium

A. Missing BEGIN before the INSERT statement

B. Parameters should not have IN keyword

C. END keyword is not needed

D. Procedure name cannot have parameters

Solution

1. Step 1: Check procedure block structure

   Procedures must enclose statements inside BEGIN and END blocks. This code misses BEGIN before INSERT.

2. Step 2: Verify other syntax parts

   IN keyword for parameters is correct, END is needed, and procedure names can have parameters.

3. Final Answer:

   Missing BEGIN before the INSERT statement -> Option A

4. Quick Check:

   Procedures need BEGIN...END blocks = A [OK]

Hint: Always wrap procedure statements with BEGIN and END [OK]

Common Mistakes:

• Forgetting BEGIN before statements
• Removing IN keyword from parameters
• Omitting END keyword

5. You want to create a procedure UpdateUserEmail that takes a user ID and a new email, then updates the user's email in the Users table. Which of the following is the correct complete procedure?

hard

A. CREATE PROCEDURE UpdateUserEmail(IN userId INT, IN newEmail VARCHAR(100)) BEGIN UPDATE Users SET Email = newEmail WHERE Id = userId; END;

B. CREATE PROCEDURE UpdateUserEmail(userId INT, newEmail VARCHAR(100)) UPDATE Users SET Email = newEmail WHERE Id = userId;

C. CREATE PROCEDURE UpdateUserEmail(IN userId INT, IN newEmail VARCHAR(100)) UPDATE Users SET Email = newEmail WHERE Id = userId; END;

D. CREATE PROCEDURE UpdateUserEmail(IN userId INT, IN newEmail VARCHAR(100)) BEGIN UPDATE Users SET Email = 'newEmail' WHERE Id = userId; END;

Solution

1. Step 1: Check parameter declaration and statement block

   Parameters must have IN keyword and the statements must be inside BEGIN...END.

2. Step 2: Verify the UPDATE statement correctness

   CREATE PROCEDURE UpdateUserEmail(IN userId INT, IN newEmail VARCHAR(100)) BEGIN UPDATE Users SET Email = newEmail WHERE Id = userId; END; correctly uses parameters without quotes around newEmail, so it updates with the variable value. CREATE PROCEDURE UpdateUserEmail(IN userId INT, IN newEmail VARCHAR(100)) BEGIN UPDATE Users SET Email = 'newEmail' WHERE Id = userId; END; incorrectly uses quotes, making it a string literal.

3. Final Answer:

   CREATE PROCEDURE UpdateUserEmail(IN userId INT, IN newEmail VARCHAR(100)) BEGIN UPDATE Users SET Email = newEmail WHERE Id = userId; END; -> Option A

4. Quick Check:

   Parameters with IN and BEGIN...END, no quotes on variables = D [OK]

Hint: Use IN parameters and BEGIN...END; no quotes on variables [OK]

Common Mistakes:

• Omitting BEGIN...END block
• Forgetting IN keyword for parameters
• Using quotes around parameter variables in SQL