Magento2 has a lot of gems hidden in it’s code-base which sometimes surprises me, why hasn’t this been documented yet !!

Not so recently I needed a way to scan an existing table schema and create a new table using the same table schema structure but with a different name of course.

In case you might be wondering why would you do something like that, well there can be some situation like

• Creating an archive table from any existing table
• Creating temporary tables to generate data and switch the table name afterwards

Finding the solution

Before trying to create my own logic for this implementation which would suck at some point, decided to dig into the Magento code to see if there is some inspiration (any code to copy-paste) I can find

Magento did not disappoint

Started my search at the very own class responsible for creating, modifying tables and doing DDL operations and you might already guessed it right:

\Magento\Framework\DB\Adapter\AdapterInterface

The interface is implemented by:

\Magento\Framework\DB\Adapter\Pdo\Mysql

and the method which does the magic is createTableByDdl

Implementing the functionality

So, here’s how it works, the method takes 2 arguments

• $tableName this would be an existing table name whose schema you would to copy.
• $newTableName the name of the new table you would like to create based on the copied schema structure.

Now, the method does not create the new table (don’t let the method name fool you like it fooled me), but will return a table object, \Magento\Framework\DB\Ddl\Table to be precise, which would then be needed to be passed to the \Magento\Framework\DB\Adapter\AdapterInterface::createTable method as the argument, which in turn creates the table in your database.

Putting it all together

• Step - 1 : Create the table object for the new table using the existing table

/**
  * @var $adapter \Magento\Framework\DB\Adapter\AdapterInterface
  * @var $table \Magento\Framework\DB\Ddl\Table 
  */
 $table = $adapter->createTableByDdl(  
  $adapter->getTableName($sourceTable),  
  $adapter->getTableName($archiveTable)  
);

• Step - 2 : Use the table object returned to actually create the table in your database.

/**
  * @var $adapter \Magento\Framework\DB\Adapter\AdapterInterface
  */
  
$adapter->createTable($table)

Conclusion

Dig the core codebase of Magento, it will always surprise you.