for (ERXMigrationColumn column : columns) {
EOAttribute attribute = column._newAttribute(entity);
attributes.addObject(attribute);
}
entity.setPrimaryKeyAttributes(attributes);
NSArray<EOSQLExpression> expressions = schemaGeneration.dropPrimaryKeySupportStatementsForEntityGroup(new NSArray<EOEntity>(entity));
ERXMigrationDatabase._ensureNotEmpty(expressions, "drop primary key", true);
return expressions;
}
/**