How to detect if a table has rows in crystal 2008 - crystal-reports

Question

Is there a built in crystal method to detect whether the a table in a crystal report has any rows?
I have created a sub report which has some Title text in the header and a detail line with the table info.
I want to be able to supress the title text from printing if there is nothing to print.
Also, is there any way to pass this to the "master" report so that I can suppress printing the sub report completely if there is nothing to print?
Regards

Answer 1

Use Count() function.
Use it with one of your data source fields.
from Crystal Reports 2008 Help:
Overloads
Count (fld)
Count (fld, condFld)
Count (fld, condFld, cond)
Count (x)
Arguments
fld is any valid database or formula field that can be evaluated by the function.
condFld is a field used to group the values in fld by.
cond is a String indicating the type of grouping for condFld. You only specify this argument when condFld is a Date, Time, DateTime or Boolean field. For more information on the valid strings for this argument, see Conditions for summary functions .
x is an array of values that can be evaluated by the function being used.
Returns
Number
Action
Enables you to count the values that appear in your report (for a specified field). For example:
If a sales report includes all orders made and the amount of each order, you can compute the total number of orders that appear on the report (a grand total count).
If you break orders into groups (for example, orders grouped by the state that they come from), you can compute the number of orders per group (in this case, per state).
If you break orders into date or Boolean groups (for example, orders grouped by the month in which they were placed), you can compute the number of orders per group based on a particular change in the date or Boolean field (in this case, per month).
If you specify a set of individual values, you can compute the number of values in the set. For information on this kind of counting, see Array summary functions .
Examples
The following examples are applicable to both Basic and Crystal syntax:
Count({orders.AMOUNT}, {orders.CUSTOMER ID})
This formula counts the number of orders in each group of orders in the Amount field (the total orders for each customer). The orders are separated into groups whenever the value in the Customer ID field changes.
Count({orders.ORDER AMOUNT}, {orders.ORDER DATE}, "monthly")
Counts the number of orders in each group of orders in the Amount field (the total orders for each month). The orders are separated into groups whenever the value in the Date field changes to a new month.
The following examples are applicable to Crystal syntax:
If Count({orders.ORDER ID}) >= 100 Then
"Congratulations on meeting your quota!"
Else
""
Prints the congratulatory message if the number of orders is 100 or more, and prints nothing if the number of orders is less than 100.
Count([1,2,3,4,5])
Returns 5. Counts the total number of values in the array.
Note: Using this function in a formula forces the formula to be evaluated at print time.
For more information on evaluation time considerations, see Evaluation Time.