Unknown column type "double" requested. Any Doctrine type that you use has to be registered with \Doctrine\DBAL\Types\Type::addType

PHP
// This means the datatype of the column you are trying to change or modify
// is NOT SUPPORTED by doctrine/dbal. Use raw DB statement instead.

DB::statement('ALTER TABLE `table_name` MODIFY `column_name` DOUBLE(19,4) NULL');
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