Hi there,
When creating another column property in a model that makes use of the
exists(), I noticed that the exists does a "select *".
*For example, the form exists below:*
class Contact(ResourceMixin, db.Model):
__tablename__ = 'contacts'
form_contacts = db.relationship(FormContact, backref='contact',
passive_deletes=True)
form_exists = column_property(
exists().where(and_( FormContact .form_contact_id == id,
FormContact.partnership_id == partnership_id
)).label('form_contact_exist'), deferred=True
)
*prints out to be something like:*
exists(select * from form_contacts where form_contacts.form_contact_id ==
id and form_contacts. partnership_id == partnership_id)
Does the exists "stop" the query once one row is returned or does it
execute the entire select all query?
If the latter, is there a way to limit the select all to one row?
Regards,
Justin
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