When to use the columnname property in an expression?
When you create an expression, use the ColumnName property to refer to columns. For example, if the ColumnName for one column is “UnitPrice”, and another “Quantity”, the expression would be as follows: If a column is used in an expression, then the expression is said to have a dependency on that column.
How to use complex expressions in Report Builder?
Pass a parameter from a main report to a subreport. Parameters collection on the subreport. Use Subreport Properties Dialog Box, Parameters. Complex expressions can contain multiple built-in references, operators, and function calls, and appear on the design surface as < >.
How is the return type of an expression determined?
Gets or sets the expression used to filter rows, calculate the values in a column, or create an aggregate column. An expression to calculate the value of a column, or create an aggregate column. The return type of an expression is determined by the DataType of the column.
How are literal expressions expressed in a dataset?
All literal expressions must be expressed in the invariant culture locale. When DataSet parses and converts literal expressions, it always uses the invariant culture, not the current culture. String literals are identified when there are single quotes surrounding the value.
When does an expression not evaluate to a string?
When you use the SUBSTRING function, the length argument is out of range. When you use the LEN function or the TRIM function, the expression does not evaluate to a string. This includes expressions that evaluate to Char. The following example creates three columns in a DataTable.
Can a child column be referenced in an expression?
A column in a child table may be referenced in an expression by prepending the column name with Child. However, because child relationships may return multiple rows, you must include the reference to the child column in an aggregate function.
How to reference a parent table in an expression?
A parent table may be referenced in an expression by prepending the column name with Parent. For example, the Parent.Price references the parent table’s column named Price. When a child has more than one parent row, use Parent (RelationName).ColumnName.