bcquality/microsoft/knowledge/data-modeling/delete-master-data-with-trigger.md

bc-version	domain	keywords	technologies	countries	application-area
all	data-modeling	delete deleteall runtrigger ondelete master-data currency cleanup data-migration	al	w1	all

Delete master and reference data with Delete(true) so the owning table's OnDelete decides

Description

Record.Delete() and Record.DeleteAll() do not run OnDelete unless RunTrigger is true; the default is false. On a master or reference table, OnDelete is where Business Central decides whether the delete is safe and removes what the record owns. Currency.OnDelete refuses the delete while any open customer, vendor, or employee ledger entry uses the code, then deletes the currency's Currency Exchange Rate rows itself. Customer.OnDelete refuses when a job bills the customer, calls codeunit 361 MoveEntries (which refuses while ledger entries fall in an unclosed fiscal year or are still open, and otherwise detaches the closed history), and removes default dimensions, related data, and the contact link.

A cleanup, migration, or "remove obsolete codes" routine that calls Delete()/DeleteAll() without true on such a table skips all of it: it can remove a currency that open entries still use, and leaves exchange rates and other dependents orphaned. That a record looks obsolete — a superseded currency nobody posts in any more — is no evidence the guard would pass, and keeping a record that closed history still refers to is often the better choice. Where the master has a Blocked field, blocking rather than deleting is the usual way to retire it (see check-blocked-in-referencing-code-not-in-master); Currency has none.

Best Practice

Outside the owning table's own triggers, delete master and reference records with Delete(true)/DeleteAll(true) and let OnDelete raise its error, as BCApps does when it removes items (CatalogItemManagement, NewItem.Delete(true)). This is the "trigger does work the caller depends on" case of pass-false-to-insert-when-trigger-not-needed; a hand-written reference check is no substitute for the guard.

Legitimate false deletes, not in scope: the owning table's own OnDelete cascade removing its dependents (Currency.OnDelete itself calls CurrExchRate.DeleteAll(); see owning-table-must-delete-dependents-in-ondelete); temporary records and buffers; and a deliberate full reset whose caller first clears every reference itself, such as codeunit 1812 "Data Migration Del G/L Account" before a migration reload. Posted ledger entries are not master data; see do-not-modify-or-delete-posted-ledger-entries.

See sample: delete-master-data-with-trigger.good.al.

Anti Pattern

Code outside the owning table's OnDelete calls Delete()/DeleteAll() (or false) on a non-temporary master or reference table — Currency, Customer, Vendor, Item, G/L Account, or a custom equivalent with an OnDelete guard or cascade — typically from a filter on codes judged obsolete, without itself clearing every reference first.

See sample: delete-master-data-with-trigger.bad.al.

References

• Record.Delete method and Record.DeleteAll method: RunTrigger "The default value is false."
• BCApps src/Layers/W1/BaseApp/Finance/Currency/Currency.Table.al, OnDelete, lines 797-820.
• BCApps src/Layers/W1/BaseApp/Sales/Customer/Customer.Table.al, OnDelete, lines 2401-2430; src/Layers/W1/BaseApp/Utilities/MoveEntries.Codeunit.al, MoveCustEntries, lines 126-167.
• BCApps src/Layers/W1/BaseApp/Inventory/Item/Catalog/CatalogItemManagement.Codeunit.al, line 419.
• BCApps src/Layers/W1/BaseApp/System/DataMigration/DataMigrationDelGLAccount.Codeunit.al, lines 18-41.