Bug 176114 row._rownum implementation issues
This Bugzilla seeks to clarify the usage of the "row.__rownum" binding, and to track its correct implementation in BIRT Data engine. We shall define the "__rownum" binding to mean: the 0-based index of the current data row in the final result set available to a listing report item. "Final" result set means the result set after all applicable filter and sort conditions are applied. This definition implies: (1) "row.__rownum" is not available to expressions used to define a filter or sort condition. Since filtering and sorting affects the row indexes, they cannot make forward reference to the final row index. This restriction applies to all filters and sorts, including those defined on groups. (2) Group key expression can use "row.__rownum", since grouping does not change the row ordering or ID. In fact one of the common usage of the row.__rownum binding is to create row number based interval grouping (e.g., put every 20 rows in a group). BIRT should report a sensible error message if row.__rownum is found to be used in sorting or filtering. Where a row number based sort/filter is desired, the report designer is encouraged to use the Total.runningCount aggregation.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/i18n/ResourceConstants.java
public final static String ILLEGAL_PARAMETER_FUN = "data.engine.BadAggrFuncParam";
	public final static String RESET_RATE = "data.engine.ResetRateGuess";
	public final static String UNSUPPORTTED_COND_OPERATOR = "data.engine.UnsupportedCondOp";
	public final static String EXPRESSION_CANNOT_BE_NULL_OR_BLANK = "data.engine.EmptyExpression";	
			
	public final static String INVALID_JOIN_TYPE="data.engine.InvalidJoinType";
	public final static String INVALID_JOIN_OPERATOR="data.engine.InvalidJoinOperator";
	public final static String NAMED_PARAMETER_NOT_FOUND  = "data.engine.BadDataSetParamName";
	
	
	public final static String INVALID_BOUND_COLUMN_NAME = "data.engine.InvalidBoundColumnName";
	public final static String INVALID_GROUP_KEY = "data.engine.InvalidGroupKey";
	public final static String COLUMN_BINDING_NOT_EXIST = "data.engine.ColumnBindingNotExist";
	public final static String COLUMN_BINDING_CYCLE = "data.engine.ColumnBindingCycle";
	public final static String COLUMN_BINDING_REFER_TO_INEXIST_COLUMN = "data.engine.ColumnBindingReferToInexistColumn";
	public final static String COLUMN_BINDING_REFER_TO_AGGREGATION_COLUMN_BINDING_IN_PARENT_QUERY = "data.engine.ColumnBindingReferToAggregationColumnBindingInParentQuery";
	
	public final static String EXPR_INVALID_COMPUTED_COLUMN= "data.engine.BadCompColExpr";
	
	public final static String WRONG_DATA_TYPE_COMPUTED_COLUMN= "data.engine.CompCol.WrongDataType";
	public final static String WRONG_DATA_TYPE_SCRIPT_RESULT= "data.engine.ScriptResult.WrongDataType";
	
	
	public final static String INVALID_EXPRESSION_IN_FILTER = "data.engine.BadFilterExpr";
	public final static String INVALID_DEFINITION_IN_FILTER = "data.engine.BadFilterDefn";
	public final static String BAD_GROUP_EXPRESSION = "data.engine.BadGroupExpr";
	
	
	public final static String CLOB_OPEN_ERROR = "data.engine.opencloberror";