What are the steps to create a stored procedure in MySQL that includes validations and displays specific fields?

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Here are the steps to create a stored procedure in MySQL that includes validations and displays specific fields:

1. Open the MySQL console or any other SQL client.

2. Create a new database or use an existing one.

3. Create a new stored procedure using the following syntax:

CREATE PROCEDURE procedure_name (IN parameter1 datatype1, IN parameter2 datatype2)
BEGIN
-- SQL statements here
END;

1. Define the input parameters for the stored procedure. In this case, we will include two parameters: email and password.

2. Add validation code to ensure that the input parameters meet certain criteria. For example, we may want to make sure that the email is a valid email address and that the password is at least 8 characters long.

3. If the input parameters pass validation, we can execute a SQL query to retrieve specific fields from the database. For example, we may want to retrieve the user's name, email, and account information.

4. Finally, we can display the results of the query using PRINT or SELECT statements.

Here's an example of what the code might look like:

CREATE PROCEDURE get_user_info (IN email VARCHAR(255), IN password VARCHAR(255))
BEGIN
  DECLARE user_name VARCHAR(255);
  DECLARE user_email VARCHAR(255);
  DECLARE account_info VARCHAR(255);

  -- Validate input parameters
  IF email NOT REGEXP '^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$' THEN
    SELECT "Invalid email address" AS error_message;
    RETURN;
  END IF;

  IF LENGTH(password) < 8 THEN
    SELECT "Password must be at least 8 characters long" AS error_message;
    RETURN;
  END IF;

  -- Execute SQL query
  SELECT name, email, account_info INTO user_name, user_email, account_info
  FROM users
  WHERE email = email AND password = password;

  -- Display results
  IF user_name IS NOT NULL THEN
    SELECT user_name, user_email, account_info;
  ELSE
    SELECT "No user found with email and password" AS error_message;
  END IF;
END;

With this stored procedure, we can pass in an email and password, and the procedure will validate the input parameters and retrieve the user's name, email, and account information from the database. If there are any errors or if no user is found, the procedure will return an error message.