void
UnqliteCursor::remove()
{
int rc = unqlite_kv_cursor_delete_entry(this->_cursor);
if (rc != UNQLITE_OK)
throw UnqliteException(rc, this->_db);
}
/*
* Drop a collection from the KV storage engine and the underlying
* unqlite VM.
*/
UNQLITE_PRIVATE int unqliteDropCollection(unqlite_col *pCol)
{
unqlite_vm *pVm = pCol->pVm;
jx9_int64 nId;
int rc;
/* Reset the cursor */
unqlite_kv_cursor_reset(pCol->pCursor);
/* Seek the cursor to the desired location */
rc = unqlite_kv_cursor_seek(pCol->pCursor,
SyStringData(&pCol->sName),SyStringLength(&pCol->sName),
UNQLITE_CURSOR_MATCH_EXACT
);
if( rc == UNQLITE_OK ){
/* Remove the record from the storage engine */
rc = unqlite_kv_cursor_delete_entry(pCol->pCursor);
}
if( rc != UNQLITE_OK ){
unqliteGenErrorFormat(pCol->pVm->pDb,
"Cannot remove collection '%z' due to a read-only Key/Value storage engine",
&pCol->sName
);
return rc;
}
/* Drop collection records */
for( nId = 0 ; nId < pCol->nLastid ; ++nId ){
unqliteCollectionDropRecord(pCol,nId,0,0);
}
/* Cleanup */
CollectionCacheRelease(pCol);
SyBlobRelease(&pCol->sHeader);
SyBlobRelease(&pCol->sWorker);
SyMemBackendFree(&pVm->sAlloc,(void *)SyStringData(&pCol->sName));
unqliteReleaseCursor(pVm->pDb,pCol->pCursor);
/* Unlink */
if( pCol->pPrevCol ){
pCol->pPrevCol->pNextCol = pCol->pNextCol;
}else{
sxu32 iBucket = pCol->nHash & (pVm->iColSize - 1);
pVm->apCol[iBucket] = pCol->pNextCol;
}
if( pCol->pNextCol ){
pCol->pNextCol->pPrevCol = pCol->pPrevCol;
}
MACRO_LD_REMOVE(pVm->pCol,pCol);
pVm->iCol--;
SyMemBackendPoolFree(&pVm->sAlloc,pCol);
return UNQLITE_OK;
}
/*
* Drop a record from a given collection.
*/
UNQLITE_PRIVATE int unqliteCollectionDropRecord(
unqlite_col *pCol, /* Target collection */
jx9_int64 nId, /* Unique ID of the record to be droped */
int wr_header, /* True to alter collection header */
int log_err /* True to log error */
)
{
SyBlob *pWorker = &pCol->sWorker;
int rc;
/* Reset the working buffer */
SyBlobReset(pWorker);
/* Prepare the unique ID for this record */
SyBlobFormat(pWorker,"%z_%qd",&pCol->sName,nId);
/* Reset the cursor */
unqlite_kv_cursor_reset(pCol->pCursor);
/* Seek the cursor to the desired location */
rc = unqlite_kv_cursor_seek(pCol->pCursor,
SyBlobData(pWorker),SyBlobLength(pWorker),
UNQLITE_CURSOR_MATCH_EXACT
);
if( rc != UNQLITE_OK ){
return rc;
}
/* Remove the record from the storage engine */
rc = unqlite_kv_cursor_delete_entry(pCol->pCursor);
/* Finally, Remove the record from the cache */
unqliteCollectionCacheRemoveRecord(pCol,nId);
if( rc == UNQLITE_OK ){
pCol->nTotRec--;
if( wr_header ){
/* Relect in the collection header */
rc = CollectionSetHeader(0,pCol,-1,pCol->nTotRec,0);
}
}else if( rc == UNQLITE_NOTIMPLEMENTED ){
if( log_err ){
unqliteGenErrorFormat(pCol->pVm->pDb,
"Cannot delete record from collection '%z' due to a read-only Key/Value storage engine",
&pCol->sName
);
}
}
return rc;
}
