About regular expression
Strings in JPQL and Criteria Queries
Explains string expressions in JPQL queries, including LIKE, LOCATE, LOWER, UPPER, TRIM, CONCAT and SUBSTRING.... is always the string to check for a match (usually a path expression) and the right operand is always the pattern (usually a parameter or ... be useful when there is a need for pattern matching using regular expressions (which are more powerful than the LIKE operator). ...
[ODB1] Chapter 7 - JDOQL Queries
Explains how to use JDOQL, the Java/JDO Query Language.... a persistent class) A filter, which is a boolean expression in a Java like syntax The query result is a subset of objects ... ... ) for a case in which the candidate collection is a regular Java collection, rather than an Extent : Query newQuery ( ...
Issue with DISTINCT Select
It is getting more and more frustrating :( We've introduced distinct select instead of regular selection in our code (no changes else) and suddenly receive invalid identifiers in queries exceptions in various queries. Here's the stacktrace: ... :( We've introduced distinct select instead of regular selection in our code (no changes else) and suddenly receive invalid ... Caused by: com.objectdb.o.UserException: Invalid order expression '$3' for distinct results at ... are strict rules regarding what is allowed in the ORDER BY expression. You didn't provide a query so it is impossible to say if the ...
FROM clause (JPQL / Criteria API)
Explains how to use the FROM clause and JOIN expressions in a JPA/JPQL query.... types at the WHERE clause level by using a type expression . For example, in the following query, c iterates over ... c . capital The JOIN FETCH expression is not a regular JOIN and it does not define a JOIN variable. Its only purpose is ...
Optimization of Map Queries
hi! I am having loads and loads of occurrences of something like ((com.test.MyEntity) $1.map.get('com.test.MyEntity')).someProperty ... ((com.test.MyEntity) $1.map.get('com.test.MyEntity')).someOtherProperty .. ((com.test.MyEntity) $1.map.get('com.test.MyEntity')).someMoreProperties I need to use full qualified names for casting as well as for the map keys because same entity simple names may occur multiple times. Now I've got two questions: ... introducing a variable using JOIN that is bound to the expression could help (at least the method will be invoked once). ... object oriented models, usage of map is something pretty regular..) Alex edit ...
