JDO Query Guide (v5.2) Table of Contents Query API . 2 Creating a query . 2 Closing a query . 3 Named Query . 3 Query Extensions . 5 Setting query parameters. 6 Compiling a query . 6 Executing a query . 6 Controlling the execution : FetchPlan . 7 ignoreCache(), setIgnoreCache(). 9 Control over locking of fetched objects . 9 Timeout on query execution for reads . 9 Timeout on query execution for writes . 10 Extension: Loading Large Result Sets at Commit() . 10 Extension: Caching of Results . 10 Extension: Size of Large Result Sets . 10 Extension: Type of Result Set (RDBMS). 11 Extension: Result Set Control (RDBMS). 11 JDOQL . 13 JDOQL Single-String syntax . 13 Candidate Class. 14 Filter . 15 Fields/Properties . 16 Methods . 17 Literals . 35 Parameters. 35 Variables. 37 Imports . 38 IF ELSE expressions. 39 Operators . 39 instanceof. 40 casting. 40 Subqueries. 40 Result clause . 43 Result Class . 44 Grouping of Results . 45 Ordering of Results . 46 Range of Results . 46 JDOQL In-Memory queries . 47 Update/Delete queries. 48 Deletion by Query . 48 Bulk Delete. 48 Bulk Update . 48 JDOQL Strictness . 49 JDOQL : SQL Generation for RDBMS . 49 JDOQL Typed . 50 Preparation . 50 Query Classes . 51 Query API - Filtering . ..