ODPI-C Function Round-Trips¶

The following table identifies if round-trips to the database are required when calling each of the functions that ODPI-C supports. A round-trip is defined as the trip from the Oracle Client libraries (used by ODPI-C) to the database and back.

Function	Round-Trips?	Notes
`dpiConn_addRef()`	No
`dpiConn_beginDistribTrans()`	Yes
`dpiConn_breakExecution()`	Yes
`dpiConn_changePassword()`	Yes
`dpiConn_close()`	Maybe	If the connection was acquired from a pool, a round-trip is only required if the parameter mode is set to the value DPI_MODE_CONN_CLOSE_DROP. For standalone connections, a round-trip is always required. If there is an open transaction, a round-trip is also required to perform the implicit rollback that takes place.
`dpiConn_commit()`	Yes
`dpiConn_create()`	Maybe	If a standalone connection is being created, one round-trip is required. If a connection is being acquired from a pool, no round-trips are required if an unused connection is available in the pool; otherwise, a round trip is required for each connection that is added to the pool (see `dpiPoolCreateParams.sessionIncrement`).
`dpiConn_deqObject()`	Yes
`dpiConn_enqObject()`	Yes
`dpiConn_getCallTimeout()`	No
`dpiConn_getCurrentSchema()`	No
`dpiConn_getEdition()`	No
`dpiConn_getEncodingInfo()`	No
`dpiConn_getExternalName()`	No
`dpiConn_getHandle()`	No
`dpiConn_getInternalName()`	No
`dpiConn_getIsHealthy()`	No
`dpiConn_getLTXID()`	No
`dpiConn_getObjectType()`	Maybe	If the type information is already available in the Oracle Client object cache, only one round trip is required; otherwise, two round-trips are required unless the type contains embedded types or is a collection. In that case additional round-trips are required to fetch the additional type information.
`dpiConn_getOciAttr()`	No
`dpiConn_getServerVersion()`	Maybe	The first call when requesting the release string always requires a round-trip. If the release string is not requested and Oracle Client 20.3 or higher is being used, no round-trip is required. Similarly for earlier versions, if the release string is not requested and a pooled connection is used that previously had a call to this function made, no round-trip is required; otherwise, a round-trip is required. Subsequent calls with any client version do not require a round-trip.
`dpiConn_getSodaDb()`	Maybe	An internal call to check the server version is made. The notes on the function `dpiConn_getServerVersion()` apply.
`dpiConn_getStmtCacheSize()`	No
`dpiConn_newDeqOptions()`	No
`dpiConn_newEnqOptions()`	No
`dpiConn_newMsgProps()`	No
`dpiConn_newQueue()`	No
`dpiConn_newTempLob()`	Yes
`dpiConn_newVar()`	No
`dpiConn_ping()`	Yes
`dpiConn_prepareDistribTrans()`	Yes
`dpiConn_prepareStmt()`	No
`dpiConn_release()`	Maybe	If the number of references exceeds 1 or the connection has already been closed by a call to `dpiConn_close()` then no round-trips are required; otherwise, the connection is closed at this point and the notes on the function `dpiConn_close()` apply.
`dpiConn_rollback()`	Yes
`dpiConn_setAction()`	No
`dpiConn_setCallTimeout()`	No
`dpiConn_setClientIdentifier()`	No
`dpiConn_setClientInfo()`	No
`dpiConn_setCurrentSchema()`	No
`dpiConn_setDbOp()`	No
`dpiConn_setEcontextId()`	No
`dpiConn_setExternalName()`	No
`dpiConn_setInternalName()`	No
`dpiConn_setModule()`	No
`dpiConn_setOciAttr()`	No
`dpiConn_setStmtCacheSize()`	No
`dpiConn_shutdownDatabase()`	Yes
`dpiConn_startupDatabase()`	Yes
`dpiConn_startupDatabaseWithPfile()`	Yes
`dpiConn_subscribe()`	Yes
`dpiConn_tpcBegin()`	Yes
`dpiConn_tpcCommit()`	Yes
`dpiConn_tpcEnd()`	Yes
`dpiConn_tpcForget()`	Yes
`dpiConn_tpcPrepare()`	Yes
`dpiConn_tpcRollback()`	Yes
`dpiConn_unsubscribe()`	Yes
`dpiContext_createWithParams()`	No
`dpiContext_destroy()`	No
`dpiContext_getClientVersion()`	No
`dpiContext_getError()`	No
`dpiContext_initCommonCreateParams()`	No
`dpiContext_initConnCreateParams()`	No
`dpiContext_initPoolCreateParams()`	No
`dpiContext_initSodaOperOptions()`	No
`dpiContext_initSubscrCreateParams()`	No
`dpiData_getBool()`	No
`dpiData_getBytes()`	No
`dpiData_getDouble()`	No
`dpiData_getFloat()`	No
`dpiData_getInt64()`	No
`dpiData_getIntervalDS()`	No
`dpiData_getIntervalYM()`	No
`dpiData_getIsNull()`	No
`dpiData_getJson()`	No
`dpiData_getJsonArray()`	No
`dpiData_getJsonObject()`	No
`dpiData_getLOB()`	No
`dpiData_getObject()`	No
`dpiData_getStmt()`	No
`dpiData_getTimestamp()`	No
`dpiData_getUint64()`	No
`dpiData_setBool()`	No
`dpiData_setBytes()`	No
`dpiData_setDouble()`	No
`dpiData_setFloat()`	No
`dpiData_setInt64()`	No
`dpiData_setIntervalDS()`	No
`dpiData_setIntervalYM()`	No
`dpiData_setLOB()`	No
`dpiData_setNull()`	No
`dpiData_setObject()`	No
`dpiData_setStmt()`	No
`dpiData_setTimestamp()`	No
`dpiData_setUint64()`	No
`dpiDeqOptions_addRef()`	No
`dpiDeqOptions_getCondition()`	No
`dpiDeqOptions_getConsumerName()`	No
`dpiDeqOptions_getCorrelation()`	No
`dpiDeqOptions_getMode()`	No
`dpiDeqOptions_getMsgId()`	No
`dpiDeqOptions_getNavigation()`	No
`dpiDeqOptions_getTransformation()`	No
`dpiDeqOptions_getVisibility()`	No
`dpiDeqOptions_getWait()`	No
`dpiDeqOptions_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiDeqOptions_setCondition()`	No
`dpiDeqOptions_setConsumerName()`	No
`dpiDeqOptions_setCorrelation()`	No
`dpiDeqOptions_setDeliveryMode()`	No
`dpiDeqOptions_setMode()`	No
`dpiDeqOptions_setMsgId()`	No
`dpiDeqOptions_setNavigation()`	No
`dpiDeqOptions_setTransformation()`	No
`dpiDeqOptions_setVisibility()`	No
`dpiDeqOptions_setWait()`	No
`dpiEnqOptions_addRef()`	No
`dpiEnqOptions_getTransformation()`	No
`dpiEnqOptions_getVisibility()`	No
`dpiEnqOptions_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiEnqOptions_setDeliveryMode()`	No
`dpiEnqOptions_setTransformation()`	No
`dpiEnqOptions_getVisibility()`	No
`dpiJson_addRef()`	No
`dpiJson_getValue()`	Maybe	A round trip is needed if the JSON data has not yet been fetched from the server.
`dpiJson_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiJson_setFromText()`	No
`dpiJson_setValue()`	No
`dpiLob_addRef()`	No
`dpiLob_close()`	Maybe	If the LOB is a temporary LOB, one round-trip is required to free the temporary LOB; otherwise, no round-trips are required.
`dpiLob_closeResource()`	Yes
`dpiLob_copy()`	Yes
`dpiLob_getBufferSize()`	No
`dpiLob_getChunkSize()`	Yes
`dpiLob_getDirectoryAndFileName()`	No
`dpiLob_getFileExists()`	Yes
`dpiLob_getIsResourceOpen()`	Yes
`dpiLob_getSize()`	Yes
`dpiLob_openResource()`	Yes
`dpiLob_readBytes()`	Yes
`dpiLob_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiLob_setDirectoryAndFileName()`	No
`dpiLob_setFromBytes()`	Yes
`dpiLob_trim()`	Yes
`dpiLob_writeBytes()`	Yes
`dpiMsgProps_addRef()`	No
`dpiMsgProps_getCorrelation()`	No
`dpiMsgProps_getDelay()`	No
`dpiMsgProps_getDeliveryMode()`	No
`dpiMsgProps_getEnqTime()`	No
`dpiMsgProps_getExceptionQ()`	No
`dpiMsgProps_getExpiration()`	No
`dpiMsgProps_getMsgId()`	No
`dpiMsgProps_getNumAttempts()`	No
`dpiMsgProps_getOriginalMsgId()`	No
`dpiMsgProps_getPayload()`	No
`dpiMsgProps_getPriority()`	No
`dpiMsgProps_getState()`	No
`dpiMsgProps_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiMsgProps_setCorrelation()`	No
`dpiMsgProps_setDelay()`	No
`dpiMsgProps_setExceptionQ()`	No
`dpiMsgProps_setExpiration()`	No
`dpiMsgProps_setOriginalMsgId()`	No
`dpiMsgProps_setPayloadBytes()`	No
`dpiMsgProps_setPayloadObject()`	No
`dpiMsgProps_setPriority()`	No
`dpiObject_addRef()`	No
`dpiObject_appendElement()`	No
`dpiObject_copy()`	No
`dpiObject_deleteElementByIndex()`	No
`dpiObject_getAttributeValue()`	No
`dpiObject_getElementExistsByIndex()`	No
`dpiObject_getElementValueByIndex()`	No
`dpiObject_getFirstIndex()`	No
`dpiObject_getLastIndex()`	No
`dpiObject_getNextIndex()`	No
`dpiObject_getPrevIndex()`	No
`dpiObject_getSize()`	No
`dpiObject_release()`	Maybe	No round trips are required unless the last reference is being released, the internal reference to the object type is the last reference being released and the object type’s internal reference to the connection is the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiObject_setAttributeValue()`	No
`dpiObject_setElementValueByIndex()`	No
`dpiObject_trim()`	No
`dpiObjectAttr_addRef()`	No
`dpiObjectAttr_getInfo()`	No
`dpiObjectAttr_release()`	Maybe	No round trips are required unless the last reference is being released, the internal reference to the object type is the last reference being released and the object type’s internal reference to the connection is the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiObjectType_addRef()`	No
`dpiObjectType_createObject()`	No
`dpiObjectType_getAttributes()`	No
`dpiObjectType_getInfo()`	No
`dpiObjectType_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiPool_acquireConnection()`	Maybe	No round-trips are required if an unused connection is available in the pool; otherwise, a round trip is required for each connection that is added to the pool (see `dpiPoolCreateParams.sessionIncrement`). A round-trip may also be required if a PL/SQL fixup callback is specified (see `dpiPoolCreateParams.plsqlFixupCallback`).
`dpiPool_addRef()`	No
`dpiPool_close()`	Maybe	One round trip is required for each session in the pool that needs to be closed.
`dpiPool_create()`	Maybe	One round trip is required for each session that is initially added to the pool (see `dpiPoolCreateParams.minSessions`).
`dpiPool_getBusyCount()`	No
`dpiPool_getEncodingInfo()`	No
`dpiPool_getGetMode()`	No
`dpiPool_getMaxLifetimeSession()`	No
`dpiPool_getMaxSessionsPerShard()`	No
`dpiPool_getOpenCount()`	No
`dpiPool_getPingInterval()`	No
`dpiPool_getSodaMetadataCache()`	No
`dpiPool_getStmtCacheSize()`	No
`dpiPool_getTimeout()`	No
`dpiPool_getWaitTimeout()`	No
`dpiPool_reconfigure()`	Maybe	If the minimum size of the pool is not being increased, no round-trips are required; otherwise, round-trips are required for each session in the pool that needs to be added to reach the new minimum.
`dpiPool_release()`	Maybe	If the number of references exceeds 1 or the pool has already been closed by a call to `dpiPool_close()` then no round-trips are required; otherwise, the pool is closed at this point and the notes on the function `dpiPool_close()` apply.
`dpiPool_setGetMode()`	No
`dpiPool_setMaxLifetimeSession()`	No
`dpiPool_setMaxSessionsPerShard()`	No
`dpiPool_setPingInterval()`	No
`dpiPool_setSodaMetadataCache()`	No
`dpiPool_setStmtCacheSize()`	No
`dpiPool_setTimeout()`	No
`dpiPool_setWaitTimeout()`	No
`dpiQueue_addRef()`	No
`dpiQueue_deqMany()`	Yes
`dpiQueue_deqOne()`	Yes
`dpiQueue_enqMany()`	Yes
`dpiQueue_enqOne()`	Yes
`dpiQueue_getDeqOptions()`	No
`dpiQueue_getEnqOptions()`	No
`dpiQueue_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiRowid_addRef()`	No
`dpiRowid_getStringValue()`	No
`dpiRowid_release()`	No
`dpiSodaColl_addRef()`	No
`dpiSodaColl_createIndex()`	Yes
`dpiSodaColl_drop()`	Yes
`dpiSodaColl_dropIndex()`	Yes
`dpiSodaColl_find()`	Yes
`dpiSodaColl_findOne()`	Yes
`dpiSodaColl_getDataGuide()`	Yes
`dpiSodaColl_getDocCount()`	Yes
`dpiSodaColl_getMetadata()`	No
`dpiSodaColl_getName()`	No
`dpiSodaColl_insertMany()`	Yes
`dpiSodaColl_insertManyWithOptions()`	Yes
`dpiSodaColl_insertOne()`	Yes
`dpiSodaColl_insertOneWithOptions()`	Yes
`dpiSodaColl_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiSodaColl_remove()`	Yes
`dpiSodaColl_replaceOne()`	Yes
`dpiSodaColl_save()`	Yes
`dpiSodaColl_saveWithOptions()`	Yes
`dpiSodaColl_truncate()`	Yes
`dpiSodaCollCursor_addRef()`	No
`dpiSodaCollCursor_close()`	No
`dpiSodaCollCursor_getNext()`	Yes
`dpiSodaCollCursor_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiSodaDb_addRef()`	No
`dpiSodaDb_createCollection()`	Maybe	If the SODA metadata cache has been enabled and no metadata has been specified, a round trip is not required after the first time that a collection with a particular name is opened.
`dpiSodaDb_createDocument()`	No
`dpiSodaDb_freeCollectionNames()`	No
`dpiSodaDb_getCollections()`	Yes
`dpiSodaDb_getCollectionNames()`	Yes
`dpiSodaDb_openCollection()`	Maybe	If the SODA metadata cache has been enabled, a round trip is not required after the first time that a collection with a particular name is opened.
`dpiSodaDb_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiSodaDoc_addRef()`	No
`dpiSodaDoc_getContent()`	No
`dpiSodaDoc_getCreatedOn()`	No
`dpiSodaDoc_getKey()`	No
`dpiSodaDoc_getLastModified()`	No
`dpiSodaDoc_getMediaType()`	No
`dpiSodaDoc_getVersion()`	No
`dpiSodaDoc_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiSodaDocCursor_addRef()`	No
`dpiSodaDocCursor_close()`	No
`dpiSodaDocCursor_getNext()`	Yes
`dpiSodaDocCursor_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiStmt_addRef()`	No
`dpiStmt_bindByName()`	No
`dpiStmt_bindByPos()`	No
`dpiStmt_bindValueByName()`	No
`dpiStmt_bindValueByPos()`	No
`dpiStmt_close()`	No
`dpiStmt_define()`	No
`dpiStmt_defineValue()`	No
`dpiStmt_deleteFromCache()`	No
`dpiStmt_execute()`	Yes
`dpiStmt_executeMany()`	Yes
`dpiStmt_fetch()`	Maybe	An internal array of rows corresponding to the value set by a call to `dpiStmt_setFetchArraySize()` is maintained. A round trip is only required when this array has been exhausted and new rows are required to be fetched from the database.
`dpiStmt_fetchRows()`	Maybe	An internal array of rows corresponding to the value set by a call to `dpiStmt_setFetchArraySize()` is maintained. If any rows exist in this array, no round trip is required; otherwise, a round trip is required.
`dpiStmt_getBatchErrorCount()`	No
`dpiStmt_getBatchErrors()`	No
`dpiStmt_getBindCount()`	No
`dpiStmt_getBindNames()`	No
`dpiStmt_getFetchArraySize()`	No
`dpiStmt_getImplicitResult()`	No
`dpiStmt_getInfo()`	No
`dpiStmt_getLastRowid()`	No
`dpiStmt_getNumQueryColumns()`	No
`dpiStmt_getOciAttr()`	No
`dpiStmt_getPrefetchRows()`	No
`dpiStmt_getQueryInfo()`	No
`dpiStmt_getQueryValue()`	No
`dpiStmt_getRowCount()`	No
`dpiStmt_getRowCounts()`	No
`dpiStmt_getSubscrQueryId()`	No
`dpiStmt_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiStmt_scroll()`	Yes
`dpiStmt_setFetchArraySize()`	No
`dpiStmt_setOciAttr()`	No
`dpiStmt_setPrefetchRows()`	No
`dpiSubscr_addRef()`	No
`dpiSubscr_prepareStmt()`	No
`dpiSubscr_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiVar_addRef()`	No
`dpiVar_copyData()`	No
`dpiVar_getNumElementsInArray()`	No
`dpiVar_getReturnedData()`	No
`dpiVar_getSizeInBytes()`	No
`dpiVar_release()`	Maybe	No round trips are required unless the last reference is being released and the internal reference to the connection is also the last reference to that connection. In that case, the notes on the function `dpiConn_release()` apply.
`dpiVar_setFromBytes()`	Maybe	If the variable refers to a LOB, one round-trip is required; otherwise, no round trips are required.
`dpiVar_setFromJson()`	No
`dpiVar_setFromLob()`	No
`dpiVar_setFromObject()`	No
`dpiVar_setFromRowid()`	No
`dpiVar_setFromStmt()`	No
`dpiVar_setNumElementsInArray()`	No