NAME¶
CREATE SET - Create Slony-I replication set
SYNOPSIS¶
CREATE SET (options);
DESCRIPTION¶
In the Slony-I replication system, replicated tables are organized in sets. As a
general rule of thumb, a set should contain all the tables of one application,
that have relationships. In a well designed application, this is equal to all
the tables in one schema.
The smallest unit one node can subscribe for replication from another node is a
set. A set always has an origin. In classical replication terms, that would be
the ‘master.’ Since in Slony-I a node can be the
‘master’ over one set, while receiving replication data in the
‘slave’ role for another at the same time, this terminology may
easily become misleading and should therefore be replaced with ‘set
origin’ and ‘subscriber’.
- ID = ival
- ID of the set to be created.
- ORIGIN = ival
- Initial origin node of the set.
- COMMENT = 'string'
- A descriptive text added to the set entry.
If none is provided, a default value is set; A replication set so boring
no one thought to give it a name.
This uses “schemadocstoreset(p_set_comment integer, p_set_id
text)” [not available as a man page] .
EXAMPLE¶
CREATE SET ( ID = 1,
ORIGIN = 1,
COMMENT = 'Tables for ticketing system' );
LOCKING BEHAVIOUR ¶
No application-visible locking should take place.
SLONIK EVENT CONFIRMATION BEHAVIOUR ¶
Slonik waits for the command submitted to the previous event node to be
confirmed on the specified event node before submitting this command. Slonik
will also wait until any outstanding DROP SET commands are confirmed by all
nodes before it submits the CREATE SET command.
This command was introduced in Slony-I 1.0
Until version 1.2, it would crash if no comment was provided.