Use ADD EXTTRAIL to create a trail for online processing on the local system and:

• Associate it with an Extract group.

• Assign a maximum file size.

See EXTTRAIL in the Reference for Oracle GoldenGate

Syntax

ADD EXTTRAIL trail_name, EXTRACT group_name
[, MEGABYTES n]
[SEQNO n]

trail_name

A two character trail name. It is recommended that both the characters be alphabets, but the first character must not be a number. Oracle GoldenGate appends this name with a nine-digit sequence number whenever a new file is created.

The trail name can also be prefixed with a directory. For example, a trail named north/ea would have trail files named ea000000000, ea000000001 in the$OGG_DATA_HOME/north subdirectory.

group_name

The name of the Extract group to which the trail is bound. A trail can only be assigned to one Extract. Multiple Extracts cannot write to the same trail. However, one Extract can write to multiple distinct trails if needed, but this is not normally required.

MEGABYTES n

Valid for Extract. The maximum size, in megabytes, of each trail file in the sequence. The default is 500MB and the maximum value is 2000MB.

SEQNOn

Specifies that the first file in the trail will start with the specified trail sequence number. Do not include any zero padding. For example, to start at sequence 3 of a trail named tr, specify SEQNO 3. The actual file would be named /ea000000003. This option can be used during troubleshooting when Replicat needs to be repositioned to a certain trail sequence number. It eliminates the need to alter Replicat to read the required sequence number. The default value is 1.

Limitations

When capturing from a MySQL database enabled for group replication, only one trail is allowed for an Extract.

Examples

ADD EXTTRAIL north/ea, EXTRACT exte, MEGABYTES 200

The following command creates a trail name ea using the Admin Client:

ADD EXTTRAIL north/ea EXTRACT exte MEGABYTES 1500

The output is displayed as follows:

2019-11-20T23:49:19Z  INFO    OGG-08100  EXTTRAIL added.