edmiStartModelWriteTransaction

EdmiError edmiStartModelWriteTransaction(SdaiModel modelID);

Reserves exclusive write privileges to a model. Any number of clients may open a model for write access at the same time. This is possible because all persistent changes within model must be done within a model write transaction. Conflicts are avoided by only allowing one open model write transaction within a model at any point of time. If a client attempts to start a model write transaction while an other client has already reserved exclusive write privileges for him self by starting a model write transaction, the first client will have to wait until the ongoing transaction is either committed or aborted. In order to start a model write transaction, the model must be opened for write. Ordinary transactions may be nested within a model write transaction with edmiStartTransaction. However, model write transactions may not be nested within ordinary transactions. Closing a model write transaction is done by one of the following EDMInterface operations; edmiCommitTransaction, edmiAbortTransaction, edmiCommitAllTransactions, edmiAbortAllTransactions

Arguments

Return Value

Options

Example

EdmiError rstat;
 SdaiModel modId;
 . . .
 modeId = edmiGetModelBN("ourRepository", "ourModel");
  
 /* Start outer model write X-action */
 if (edmiStartModelWriteTransaction(modId)) {
 printf("\nError %d in edmiStartModelWriteTransaction: %s, rstat, 
 edmiGetErrorText(rstat)); 
 goto error; 
 }
 /* Nested X-actions */
 edmiStartTransaction();
 . . .
 if (rstat) {
 edmiAbortTransaction();
 } else {
 edmiCommitTransaction();
 }
 /* Commit outer model write X-action */
 edmiCommitTransaction();
 . . .

See also