V$XSTREAM_CAPTURE

9.139 V$XSTREAM_CAPTURE

V$XSTREAM_CAPTURE displays information about each capture process that sends LCRs to an XStream outbound server.

Column	Datatype	Description
`SID`	`NUMBER`	Session identifier of the capture process
`SERIAL#`	`NUMBER`	Session serial number of the capture process session
`CAPTURE#`	`NUMBER`	Capture process number. A capture process is an Oracle background process prefixed by `cp`
`CAPTURE_NAME`	`VARCHAR2(128)`	Name of the capture process
`LOGMINER_ID`	`NUMBER`	Session ID of the Oracle LogMiner session associated with the capture process
`STARTUP_TIME`	`DATE`	Time when the capture process was last started
`STATE`	`VARCHAR2(551)`	State of the capture process: `INITIALIZING` - Starting up. `WAITING` `FOR` `DICTIONARY` `REDO` - Waiting for redo log files containing the dictionary build related to the first SCN to be added to the capture process session. A capture process cannot begin to scan the redo log files until all of the log files containing the dictionary build have been added. `DICTIONARY` `INITIALIZATION` - Processing a dictionary build. `MINING` (`PROCESSED` `SCN` = `scn_value`) - Mining a dictionary build at the SCN `scn_value`. `LOADING` (step `X` of `Y`) - Processing information from a dictionary build and currently at step `X` in a process that involves `Y` steps, where `X` and `Y` are numbers. `CAPTURING` `CHANGES` - Scanning the redo log for changes that satisfy the capture process rule sets. `WAITING` `FOR` `REDO` - Waiting for new redo log files to be added to the capture process session. The capture process has finished processing all of the redo log files added to its session. This state is possible if there is no activity at a source database. For a downstream capture process, this state is possible if the capture process is waiting for new log files to be added to its session. `EVALUATING` `RULE` - Evaluating a change against a capture process rule set. `CREATING` `LCR` - Converting a change into an LCR. `ENQUEUING` `MESSAGE` - Enqueuing an LCR that satisfies the capture process rule sets into the capture process queue. `PAUSED` `FOR` `FLOW` `CONTROL` - Unable to enqueue LCRs either because of low memory or because propagations and outbound servers are consuming messages slower than the capture process is creating them. This state indicates flow control that is used to reduce spilling of captured LCRs when propagation or apply has fallen behind or is unavailable. `WAITING` `FOR` `THE` `BUFFERED` `QUEUE` `TO` `SHRINK` - Waiting for the buffered queue to change to a smaller size. The buffered queue shrinks when there is a memory limitation or when an administrator reduces its size. `WAITING` `FOR` `n` `SUBSCRIBER`(`S`) `INITIALIZING` - Waiting for outbound servers that receive LCRs from the capture process to start, where `n` is the number of apply processes. `WAITING` `FOR` `TRANSACTION` - Waiting for LogMiner to provide more transactions. `WAITING` `FOR` `INACTIVE` `DEQUEUERS` - Waiting for the capture process's queue subscribers to start. The capture process stops enqueuing LCRs if there are no active subscribers to the queue. `SUSPENDED` `FOR` `AUTO` `SPLIT`/`MERGE` - Waiting for a merge operation to complete. `SHUTTING` `DOWN` - Stopping. `ABORTING` - Aborting.
`TOTAL_PREFILTER_DISCARDED`	`NUMBER`	Total number of prefiltered messages discarded
`TOTAL_PREFILTER_KEPT`	`NUMBER`	Total number of prefiltered messages kept
`TOTAL_PREFILTER_EVALUATIONS`	`NUMBER`	Total number of prefilter evaluations
`TOTAL_MESSAGES_CAPTURED`	`NUMBER`	Total number of redo entries passed by LogMiner to the capture process for detailed rule evaluation since the capture process last started. A capture process converts a redo entry into a message and performs detailed rule evaluation on the message when capture process prefiltering cannot discard the change.
`CAPTURE_TIME`	`DATE`	Time when the most recent message was captured
`CAPTURE_MESSAGE_NUMBER`	`NUMBER`	Number of the most recently captured message
`CAPTURE_MESSAGE_CREATE_TIME`	`DATE`	Creation time of the most recently captured message
`TOTAL_MESSAGES_CREATED`	`NUMBER`	Count associated with `ELAPSED_LCR_TIME` to calculate rate
`TOTAL_FULL_EVALUATIONS`	`NUMBER`	Count associated with `ELAPSED_RULE_TIME` to calculate rate
`TOTAL_MESSAGES_ENQUEUED`	`NUMBER`	Total number of messages enqueued since the capture process was last started
`ENQUEUE_TIME`	`DATE`	Time when the last message was enqueued
`ENQUEUE_MESSAGE_NUMBER`	`NUMBER`	Number of the last enqueued message
`ENQUEUE_MESSAGE_CREATE_TIME`	`DATE`	Creation time of the last enqueued message
`AVAILABLE_MESSAGE_NUMBER`	`NUMBER`	For local capture, the last redo SCN flushed to the log files. For downstream capture, the last SCN added to LogMiner through the archived redo log files.
`AVAILABLE_MESSAGE_CREATE_TIME`	`DATE`	For local capture, the time the SCN was written to the log file. For downstream capture, the time the most recent archived redo log file (containing the most recent SCN) was added to LogMiner.
`ELAPSED_CAPTURE_TIME`	`NUMBER`	Elapsed time (in hundredths of a second) scanning for changes in the redo log since the capture process was last started
`ELAPSED_RULE_TIME`	`NUMBER`	Elapsed time (in hundredths of a second) evaluating rules since the capture process was last started
`ELAPSED_ENQUEUE_TIME`	`NUMBER`	Elapsed time (in hundredths of a second) enqueuing messages since the capture process was last started
`ELAPSED_LCR_TIME`	`NUMBER`	Elapsed time (in hundredths of a second) creating LCRs since the capture process was last started
`ELAPSED_REDO_WAIT_TIME`	`NUMBER`	Elapsed time (in hundredths of a second) spent by the capture process in the `WAITING` `FOR` `REDO` state
`ELAPSED_PAUSE_TIME`	`NUMBER`	Elapsed flow control pause time (in hundredths of a second)
`STATE_CHANGED_TIME`	`DATE`	Time at which the state of the capture process changed
`SGA_USED`	`NUMBER`	The total amount of shared memory (in bytes) currently used by the capture process out of the amount allocated (`SGA_ALLOCATED`)
`SGA_ALLOCATED`	`NUMBER`	The total amount of shared memory (in bytes) allocated from the Streams pool for the capture process
`BYTES_OF_REDO_MINED`	`VARCHAR2(64)`	The total amount of redo data mined (in bytes) since the capture process last started
`SESSION_RESTART_SCN`	`VARCHAR2(64)`	The SCN from which the capture process started mining redo data when it was last started
`CON_ID`	`NUMBER`	The ID of the container to which the data pertains. Possible values include: `0`: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs. `1`: This value is used for rows containing data that pertain to only the root n: Where n is the applicable container ID for the rows containing data

Note:

The ELAPSED_CAPTURE_TIME, ELAPSED_RULE_TIME, ELAPSED_ENQUEUE_TIME, ELAPSED_LCR_TIME, and ELAPSED_REDO_WAIT_TIME columns are only populated if the TIMED_STATISTICS initialization parameter is set to true, or if the STATISTICS_LEVEL initialization parameter is set to TYPICAL or ALL.