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CommitTran

procedure CommitTran;

Example​

procedure ScriptEvent(var Value: Variant);
begin
  if DBCon = nil then
    raise Exception.Create('No database connection is available');
  DBCon.CommitTran;
  Value := True;
end;

Usage​

CommitTran commits and ends the current SQL transaction when transactions are enabled and one is active.

Behaviour

There is no return value distinguishing a commit from a no-op. A successful commit makes all changes enlisted on that SQL connection durable according to database/driver rules and ends the stored transaction.

Errors and quirks

  • With no active transaction, the function quietly does nothing.
  • If StartTransaction previously saw an already-active transaction, this call can commit that pre-existing transaction; no per-script ownership token exists.
  • If Velox cannot obtain the connection, the call can fail with an object-reference error. Database and driver commit errors are raised to the script.
  • Commit affects the SQL connection, not arbitrary database work performed through other connections and not external file/network effects.
  • A commit cannot be undone by a later script exception or RollbackTran.

Side effects

Can permanently publish database changes and release transaction resources/locks. It does not save the TvxDBCon module configuration.

Additional Technical Info​

CommitTran commits and ends the transaction currently held by this DB connection wrapper.

Implementation

Runtime registration maps to native vxCommitTran. When transactions are disabled it does nothing. Otherwise it obtains SQLDATA and calls VxCommitTran, which calls Delphi DBX CommitFreeAndNil only when InTransaction is true. A SQL log comment is written only when a transaction was actually committed.

Performance and concurrency

Commit can block on database logging, constraints, locks and network I/O. Do not let another execution share/control the same transaction boundary.

Related entries

External references

Created 2026-07-15