预定义常量

下列常量由此扩展定义，且仅在此扩展编译入 PHP 或在运行时动态载入时可用。

**OCI8 Function and Method Modes**
Constant	Description
`OCI_ASSOC`	Used with oci_fetch_all() and oci_fetch_array() to get results as an associative array.
`OCI_BOTH`	Used with oci_fetch_all() and oci_fetch_array() to get results as an array with both associative and number indices.
`OCI_COMMIT_ON_SUCCESS`	Statement execution mode for oci_execute() call. Automatically commit changes when the statement has succeeded.
`OCI_CRED_EXT`	Used with oci_connect() for using Oracles' External or OS authentication.
`OCI_DEFAULT`	See `OCI_NO_AUTO_COMMIT`.
`OCI_DESCRIBE_ONLY`	Statement execution mode for oci_execute(). Use this mode if you want meta data such as the column names but don't want to fetch rows from the query.
`OCI_EXACT_FETCH`	Obsolete. Statement fetch mode. Used when the application knows in advance exactly how many rows it will be fetching. This mode turns prefetching off for Oracle release 8 or later mode. The cursor is canceled after the desired rows are fetched which may result in reduced server-side resource usage.
`OCI_FETCHSTATEMENT_BY_COLUMN`	Default mode of oci_fetch_all().
`OCI_FETCHSTATEMENT_BY_ROW`	Alternative mode of oci_fetch_all().
`OCI_LOB_BUFFER_FREE`	Used with OCILob::flush to free buffers used.
`OCI_NO_AUTO_COMMIT`	Statement execution mode for oci_execute(). The transaction is not automatically committed when using this mode. For readability in new code, use this value instead of the older, equivalent `OCI_DEFAULT` constant.
`OCI_NUM`	Used with oci_fetch_all() and oci_fetch_array() to get results as an enumerated array.
`OCI_RETURN_LOBS`	Used with oci_fetch_array() to get the data value of the LOB instead of the descriptor.
`OCI_RETURN_NULLS`	Used with oci_fetch_array() to get empty array elements if the row items value is `null`.
`OCI_SEEK_CUR`	Used with OCILob::seek to set the seek position.
`OCI_SEEK_END`	Used with OCILob::seek to set the seek position.
`OCI_SEEK_SET`	Used with OCILob::seek to set the seek position.
`OCI_SYSDATE`	Obsolete.
`OCI_SYSDBA`	Used with oci_connect() to connect with the SYSDBA privilege. The `php.ini` setting oci8.privileged_connect should be enabled to use this.
`OCI_SYSOPER`	Used with oci_connect() to connect with the SYSOPER privilege. The `php.ini` setting oci8.privileged_connect should be enabled to use this.
`OCI_TEMP_BLOB`	Used with OCILob::writeTemporary to indicate that a temporary BLOB should be created.
`OCI_TEMP_CLOB`	Used with OCILob::writeTemporary to indicate that a temporary CLOB should be created.

**OCI8 Bind and Define Types**
Constant	Description
`OCI_B_BFILE`	Used with oci_bind_by_name() when binding BFILEs.
`OCI_B_BIN`	Used with oci_bind_by_name() to bind RAW values.
`OCI_B_BLOB`	Used with oci_bind_by_name() when binding BLOBs.
`OCI_B_BOL`	Used with oci_bind_by_name() to bind a PL/SQL BOOLEAN variable.
`OCI_B_CFILEE`	Used with oci_bind_by_name() when binding CFILEs.
`OCI_B_CLOB`	Used with oci_bind_by_name() when binding CLOBs.
`OCI_B_CURSOR`	Used with oci_bind_by_name() when binding cursors, previously allocated with oci_new_descriptor().
`OCI_B_INT`	Used with oci_bind_array_by_name() to bind arrays of INTEGER.
`OCI_B_NTY`	Used with oci_bind_by_name() when binding named data types.
`OCI_B_NUM`	Used with oci_bind_array_by_name() to bind arrays of NUMBER.
`OCI_B_ROWID`	Used with oci_bind_by_name() when binding ROWIDs.
`SQLT_AFC`	Used with oci_bind_array_by_name() to bind arrays of CHAR.
`SQLT_AVC`	Used with oci_bind_array_by_name() to bind arrays of VARCHAR2.
`SQLT_BDOUBLE`	Not supported.
`SQLT_BFILEE`	The same as `OCI_B_BFILE`.
`SQLT_BFLOAT`	Not supported.
`SQLT_BIN`	The same as `OCI_B_BIN`.
`SQLT_BLOB`	The same as `OCI_B_BLOB`.
`SQLT_BOL`	The same as `OCI_B_BOL`.
`SQLT_CFILEE`	The same as `OCI_B_CFILEE`.
`SQLT_CHR`	Used with oci_bind_array_by_name() to bind arrays of VARCHAR2. Also used with oci_bind_by_name().
`SQLT_CLOB`	The same as `OCI_B_CLOB`.
`SQLT_FLT`	Used with oci_bind_array_by_name() to bind arrays of FLOAT.
`SQLT_INT`	The same as `OCI_B_INT`.
`SQLT_LBI`	Used with oci_bind_by_name() to bind LONG RAW values.
`SQLT_LNG`	Used with oci_bind_by_name() to bind LONG values.
`SQLT_LVC`	Used with oci_bind_array_by_name() to bind arrays of LONG VARCHAR.
`SQLT_NTY`	The same as `OCI_B_NTY`.
`SQLT_NUM`	The same as `OCI_B_NUM`.
`SQLT_ODT`	Used with oci_bind_array_by_name() to bind arrays of LONG.
`SQLT_RDD`	The same as `OCI_B_ROWID`.
`SQLT_RSET`	The same as `OCI_B_CURSOR`.
`SQLT_STR`	Used with oci_bind_array_by_name() to bind arrays of STRING.
`SQLT_UIN`	Not supported.
`SQLT_VCS`	Used with oci_bind_array_by_name() to bind arrays of VARCHAR.

**OCI8 Descriptor Types**
Constant	Description
`OCI_DTYPE_FILE`	This flag tells oci_new_descriptor() to initialize a new FILE descriptor.
`OCI_DTYPE_LOB`	This flag tells oci_new_descriptor() to initialize a new LOB descriptor.
`OCI_DTYPE_ROWID`	This flag tells oci_new_descriptor() to initialize a new ROWID descriptor.
`OCI_D_FILE`	The same as `OCI_DTYPE_FILE`.
`OCI_D_LOB`	The same as `OCI_DTYPE_LOB`.
`OCI_D_ROWID`	The same as `OCI_DTYPE_ROWID`.

OCI8 Transparent Application Failover (TAF) Constants

常量	描述
`OCI_FO_ABORT` (int)	Failover was unsuccessful and there is no option of retrying.
`OCI_FO_BEGIN` (int)	Failover has detected a lost connection and failover is starting.
`OCI_FO_END` (int)	Failover completed successfully.
`OCI_FO_ERROR` (int)	Failover was unsuccessful but it gives the application the opportunity to handle the error and return `OCI_FO_RETRY` to retry failover.
`OCI_FO_NONE` (int)	The user has not requested a failover type.
`OCI_FO_REAUTH` (int)	An Oracle user has been re-authenticated.
`OCI_FO_RETRY` (int)	The failover should be attempted again by Oracle. In case of an error while failing over to a new connection, TAF is able to retry the failover. Typically, the application code should sleep for a while before returning `OCI_FO_RETRY`.
`OCI_FO_SELECT` (int)	The user has requested SELECT failover as well. It allows users with open cursors to continue fetching from them after failure.
`OCI_FO_SESSION` (int)	The user has requested only session failover. For example, if a user's connection is lost, then a new session is automatically created for the user on the backup. This type of failover does not attempt to recover SELECTs.
`OCI_FO_TXNAL` (int)	The user has requested a transaction failover.