When querying an entity, you may want to restrict the query based on the existence or absence of a related entity. You can do that using the following four methods:

has

Checks for the existence of a relationship when executing the query.

By default, a has constraint will only return entities that have one or more of the related entity.

getInstance( "User" ).has( "posts" ).get();

An optional operator and count can be added to the call.

getInstance( "User" ).has( "posts", ">", 2 ).get();

Nested relationships can be checked by passing a dot-delimited string of relationships.

getInstance( "User" ).has( "posts.comments" ).get();

doesntHave

Checks for the absence of a relationship when executing the query.

By default, a doesntHave constraint will only return entities that have zero of the related entity.

getInstance( "User" ).doesntHave( "posts" ).get();

An optional operator and count can be added to the call.

getInstance( "User" ).doesntHave( "posts", "<=", 1 ).get();

Nested relationships can be checked by passing a dot-delimited string of relationships.

getInstance( "User" ).doesntHave( "posts.comments" ).get();

whereHas

When you need to have more control over the relationship constraint, you can use whereHas. This method operates similarly to has but also accepts a callback to configure the relationship constraint.

The whereHas callback is passed a builder instance configured according to the relationship. You may call any entity or query builder methods on it as usual.

getInstance( "User" )
    .whereHas( "posts", function( q ) {
	      q.where( "body", "like", "%different%" );
    } )
		.get();

When you specify a nested relationship, the builder instance is configured for the last relationship specified.

getInstance( "User" )
    .whereHas( "posts.comments", function( q ) {
	      q.where( "body", "like", "%great%" );
	  } )
	  .get();

An optional operator and count can be added to the call, as well.

getInstance( "User" )
    .whereHas( "posts.comments", function( q ) {
	      q.where( "body", "like", "%great%" );
	  }, ">", 2 )
	  .get();

whereDoesntHave

The whereDoesntHave callback is passed a builder instance configured according to the relationship. You may call any entity or query builder methods on it as usual.

getInstance( "User" )
    .whereDoesntHave( "posts", function( q ) {
	      q.where( "body", "like", "%different%" );
    } )
		.get();

When you specify a nested relationship, the builder instance is configured for the last relationship specified.

getInstance( "User" )
    .whereDoesntHave( "posts.comments", function( q ) {
	      q.where( "body", "like", "%great%" );
	  } )
	  .get();

An optional operator and count can be added to the call, as well.

getInstance( "User" )
    .whereDoesntHave( "posts.comments", function( q ) {
	      q.where( "body", "like", "%great%" );
	  }, ">", 2 )
	  .get();