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Mysql create column if not exists

Posted on December 9, 2019
At mariaDB things are easy:
ALTER TABLE tableName ADD COLUMN IF NOT EXISTS colName INT; 

But unfortunately wont work on a MySql server. Thankfully there is a nice aswer found at https://stackoverflow.com/a/31989541/
SET @dbname = DATABASE();
SET @tablename = "tableName";
SET @columnname = "colName";
SET @preparedStatement = (SELECT IF(
  (
    SELECT COUNT(*) FROM INFORMATION_SCHEMA.COLUMNS
    WHERE
      (table_name = @tablename)
      AND (table_schema = @dbname)
      AND (column_name = @columnname)
  ) > 0,
  "SELECT 1",
  CONCAT("ALTER TABLE ", @tablename, " ADD ", @columnname, " INT(11);")
));
PREPARE alterIfNotExists FROM @preparedStatement;
EXECUTE alterIfNotExists;
DEALLOCATE PREPARE alterIfNotExists;