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QueryConstraint class

A QueryConstraint is used to narrow the set of documents returned by a Database query. QueryConstraint<!-- -->s are created by invoking endAt()<!-- -->, endBefore()<!-- -->, startAt()<!-- -->, startAfter()<!-- -->, limitToFirst()<!-- -->, limitToLast()<!-- -->, orderByChild()<!-- -->, orderByChild()<!-- -->, orderByKey() , orderByPriority() , orderByValue() or equalTo() and can then be passed to query() to create a new query instance that also contains this QueryConstraint<!-- -->.

<b>Signature:</b>

export declare abstract class QueryConstraint 

Properties

QueryConstraint.type

The type of this query constraints

<b>Signature:</b>

abstract readonly type: QueryConstraintType;