Documentation

COQuery class documentation

COQuery : NSObject

A NSPredicate-based query to be run in memory or in store as a SQL statement.

AuthorsGenerated by qmathe
Declared inCOQuery.h

Overview

COQuery is provided to search the core objects either in store through -[COStore resultDictionariesForQuery:] or in memory through the COObjectMatching protocol.

It allows to combine a predicate or a raw SQL query with various additional constraints, and control how the search results are returned.

NOTE: This API is unstable and incomplete, and SQL query support is not implemented.

Initialization

+ (COQuery *) queryWithPredicate: (NSPredicate *)aPredicate

Returns a new autoreleased query that uses a predicate.

    + (COQuery *) queryWithPredicateBlock: (BOOL(^)(id object,NSDictionary*bindings))aBlock

    Returns a new autoreleased query that uses a predicate based on a block.

    See -[NSPredicate predicateWithBlock:] .

      + (COQuery *) queryWithSQLString: (NSString *)aSQLString

      Returns a new autoreleased query that uses a SQL request.

      Note: To search the store based on the returned query is not implemented, so this method is useless presently.

        Query Representations

        - (NSPredicate *) predicate

        The predicate that expresses the query.

          - (void) setPredicate: (NSPredicate *)predicate

          The predicate that expresses the query.

            - (NSString *) SQLString

            Returns a SQL representation that can be passed to the COStore API.

              Query Constraints

              - (BOOL) matchesAgainstObjectsInMemory

              Determines whether the objects in memory should be searched directly, rather than turning the predicate into a SQL query and evaluates it against the store.

              When set to YES, the objects are loaded lazily while traversing the object graph bound the object on which the query was started with -[COObjectMatching objectsMatchingQuery:] .

              If no predicate is set, this property is ignored.

              By default, returns NO.

              See also -[COObjectMatching matchesPredicate:] .

                - (void) setMatchesAgainstObjectsInMemory: (BOOL)matchesAgainstObjectsInMemory

                Determines whether the objects in memory should be searched directly, rather than turning the predicate into a SQL query and evaluates it against the store.

                When set to YES, the objects are loaded lazily while traversing the object graph bound the object on which the query was started with -[COObjectMatching objectsMatchingQuery:] .

                If no predicate is set, this property is ignored.

                By default, returns NO.

                See also -[COObjectMatching matchesPredicate:] .