Deleting Records with DELETE

Learning Objective

By the end of this lesson, you will be able to use DELETE to remove a record that was already successfully retrieved with CHAIN, completing the basic set of native RPGLE file operations.

Simple Explanation

Just as UPDATE, covered in the previous lesson, depends on a record already having been successfully retrieved, so does DELETE: it removes whichever record was most recently retrieved for a given file, generally with CHAIN after confirming %FOUND.

dcl-f CUSTMAST disk keyed;

dcl-s custNbr packed(6:0);

custNbr = 1042;
chain custNbr CUSTMAST;
if %found(CUSTMAST);
  delete CUSTMAST;
endif;

Here, the program uses chain custNbr CUSTMAST; to retrieve the specific customer record, confirms it was actually found with %found(CUSTMAST), and only then calls delete CUSTMAST; to remove that exact record from the file. Once deleted, that customer's record no longer exists in CUSTMAST; a later CHAIN for the same customer number would no longer find it.

Why It Matters

DELETE completes the basic set of native RPGLE file operations covered in this lesson group: READ and CHAIN retrieve data, WRITE adds new records, UPDATE changes existing ones, and DELETE removes them. Together, these five operations cover the fundamental ways an RPGLE program works with stored business data, connecting directly to the conceptual update/delete subfile pattern covered earlier in this path, now grounded in the actual native operations that make it work.

Practical Example

Imagine the update/delete subfile pattern described earlier in this path, where a user marks a customer record for deletion using an option field. Behind that pattern, the RPGLE program uses exactly the sequence shown above: CHAIN to retrieve the specific customer by number, %FOUND to confirm it exists, and DELETE to actually remove it from CUSTMAST.

This is a simplified, illustrative example rather than a specific real program, but it reflects exactly how a subfile-based delete option translates into native RPGLE file operations.

Common Confusions

"Can I call DELETE without first using CHAIN?" No, for the pattern covered in this lesson. DELETE removes whichever record was most recently retrieved for that file; without a preceding successful CHAIN or READ, there is no specific record for DELETE to remove.

"Does DELETE ask for confirmation before removing a record?" No. DELETE removes the record immediately once called; any confirmation, such as the window record confirmation pattern covered earlier in this path, is something the program's own logic must handle before calling DELETE, not something DELETE provides on its own.

"Once a record is deleted, can it be recovered?" Not through any operation covered in this lesson group. DELETE removes the record from the file; recovering deleted data, if possible at all, would depend on broader backup or recovery processes entirely outside what a single RPGLE program's own operations can do.

Quick Recap

• DELETE fileName; removes whichever record was most recently retrieved, generally with CHAIN after confirming %FOUND.
• DELETE requires a record to have already been successfully retrieved, the same requirement covered for UPDATE.
• DELETE does not ask for confirmation; any confirmation logic belongs in the program before DELETE is called.
• READ, CHAIN, WRITE, UPDATE, and DELETE together form the fundamental set of native RPGLE file operations covered in this lesson group.

Try Asking the AI Tutor

Use the AI Tutor to ask follow-up questions about this lesson. For example, try asking:

• "What would happen if I called DELETE twice in a row on the same record without doing another CHAIN in between?"
• "Are there IBM i features that let a deleted record be recovered later?"