E@DBLOCKFLTBEG
Name
The E@DBLOCKFLTBEG call has the following format:
DN@<Logical>(E@DBLOCKFLTBEG)
where <Logical> identifies the database file and index to use to perform the E@DBLOCKFLTBEG call.
Description
Makes the database call and locks the record.
E@DBLOCKFLTBEG reads and locks the first database record in the range based on the values you set in the record retrieval variables (D@ fields) corresponding to the index key fields and the filter created earlier in the program.
Using the API in a Program
The database routines perform an equal condition on all D@ fields that have an assigned value—that is, all columns up to, and including, the field moved to the E@DBBEGRNG.
Input Values
| Field | Description |
|---|---|
| <Logical> | <Logical> in the E@ statement identifies the database file and index to use to perform the call. |
| Record retrieval variables (also known as D@ and D# fields) | Fill in only the D@ fields that define the appropriate range; leave empty those D@ fields that do not define the range. |
| E@DBBEGRNG | Move a number into E@DBBEGRNG in order to tell the interface which key is the last significant one defining the range. This number is equivalent to the position of the field in the index. |
| Filter value parameter | Set this parameter using a method described in Setting the Filter Parameter Value, and create the filter using the routine described in U@FLTCREATE. |
Return Values
| Field | Description |
|---|---|
| D<prefix>@NOTFOUND | The Find routines set D<prefix>@NOTFOUND to FALSE if a record is found, TRUE if a record is not found, or E@KEY@FOUND if the keys are found. |
Programming Example
This example is from PR33.
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