How to Dynamically Create Column Names in MySQL Queries with CONCAT() and Server-Side Prepared Statements?

Dynamic Column Name Creation in MySQL Queries Using CONCAT() and Server-Side Prepared Statements

Problem:

Can MySQL's CONCAT() function be utilized to dynamically create column names in a query by concatenating a fixed string with the results of a separate query?

Desired Result:

For instance, it is desired to construct column names with the following format: "column" concatenated with a number generated from another query.

Solution:

Initially, it was assumed that this operation was not feasible. However, further investigation revealed that server-side prepared statements in MySQL provide a solution. These statements enable the creation and execution of arbitrary SQL statements from dynamic strings.

Implementation:

The following example demonstrates how to achieve this dynamic column name creation:

-- Construct the dynamic query string using CONCAT()
SET @query := (
  SELECT CONCAT(
    "SELECT",
    GROUP_CONCAT(CONCAT("\n  1 AS ", COLUMN_NAME) SEPARATOR ','),
    "\nFROM DUAL"
  )
  FROM INFORMATION_SCHEMA.COLUMNS
  WHERE TABLE_NAME = 'COLUMNS'
);

-- Prepare the statement using the constructed query
PREPARE s1 FROM @query;

-- Execute the prepared statement
EXECUTE s1;

-- Deallocate the prepared statement
DEALLOCATE PREPARE s1;

This approach dynamically generates the desired column names based on the specified criteria and executes the query accordingly.

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