OP Distinct values

version 1.5

OP Distinct values (connectionID; tableID; fieldID; distinctValues) Longint

Parameter	Type		Description
connectionID	Longint		Connection ID with target server
tableID	Longint		Number of the table in the database
fieldID	Longint		Number of the (indexed) field in the table
distinctValues	Array		Array containing disinct values found in
			current selection
Function result	Longint		Error code result for the function

OP Distinct values fills distinctValues with the unique values from fieldID, which is in tableID, from the current selection.

fieldID must be the number of an indexed Alphanumeric field.

distinctValues is an array of type String, Text, Integer, Long Integer, Real, Date, or Boolean.

This function does not change the current selection or the current record.

If OP Distinct values executes successfully, it returns 0. Otherwise, this function returns one of the following errors:

Error Code	Description
-108	Not enough memory to perform this operation.
-9970	Field is not indexed.
-9971	Field number is out of range.
-9972	table number is out of range.
10128	The 4D Open for 4th Dimension package has not been initialized.
10135	Invalid parameter type.
10136	The connection does not exist.
10153	Unable to convert this type of data.
10154	This command cannot be executed right now.
10158	The field is not an indexed alphanumeric field.

This example presents the user with a list (scrollable area) of today's customers cities.

   C_LONGINT (vRecords; $ErrCode)
   C_STRING (10;vValue)
   ARRAY STRING (25; aCities;0)

   `Compute today's date
   vValue:= String ( Current date ) 

   ` Query for invoices dated of the day, on the [Invoices]Invoice date field (2;3)
   $errCode:=OP Single query (vConnectID;2;3;"=";->vValue;vRecords)

   ` Create a selection of customers for those invoices
   $errCode:=OP Many to one join (vConnectID;1;2)

   ` Load distinct (no duplicates) city names from [Customers]City (1;5) into the aCities array
   $errCode := OP Distinct values (vConnectID;1;5;aCities)

DISTINCT VALUES, OP Get one field number, OP Selection to array, OP Single query.