How Can I Dynamically Select Column Names in MySQL Based on Schema Changes?

Dynamic Column Name Selection in MySQL

When working with MySQL tables whose structures may change frequently, it can be challenging to select specific column names hardcoded in your SQL statements. To overcome this, a technique can be employed that dynamically selects column names based on the table's current schema.

In response to the presented question, a SQLFiddle example is provided:

CREATE TABLE atable (
  prefix1 VARCHAR(10)
  ,prefix2 VARCHAR(10)
  ,notprefix3 INT
  ,notprefix4 INT
);

INSERT INTO atable VALUES ('qwer qwer', 'qwerqwer', 1, 1);
INSERT INTO atable VALUES ('qwer qwer', 'asdfaasd', 1, 1);
INSERT INTO atable VALUES ('qwer qwer', 'qrt vbb', 1, 1);
INSERT INTO atable VALUES ('qwer qwer', 'sdfg sdg', 1, 1);

SELECT CONCAT('SELECT ', GROUP_CONCAT(c.COLUMN_NAME), ' FROM atable;')
INTO @query
FROM INFORMATION_SCHEMA.COLUMNS c
WHERE c.TABLE_NAME = 'atable'
  AND c.COLUMN_NAME LIKE 'prefix%'
ORDER BY c.ORDINAL_POSITION;

PREPARE stmt FROM @query;

EXECUTE stmt;

This example is useful for selecting column names that share a common prefix, such as "prefix1" and "prefix2". However, it has a few limitations:

• May require manual updates in case of schema changes
• Can only handle certain types of schema changes
• May move validation to runtime and increase the risk of errors
• Limited in its ability to handle joins and other advanced operations

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