None <espressobean...@gmail.com> writes:

> Hi,
>
> I'm searching for all of the possible parameters for setting the
> "wal_level" outlined in the PostgreSQL Streaming Replication article:
>
> https://wiki.postgresql.org/wiki/Streaming_Replication
>
> I currently see hot_standby, but I can't find a list for all of the
> parameters that setting will take. Where can I find that?

You didn't even tell us what version is relevant here but let's assume 9.6...


https://www.postgresql.org/docs/9.6/static/runtime-config-wal.html


wal_level (enum)
   
    wal_level determines how much information is written to the WAL. The 
default value is minimal, which writes only the information needed to recover 
from a crash or immediate shutdown.
    replica adds logging required for WAL archiving as well as information 
required to run read-only queries on a standby server. Finally, logical adds 
information necessary to support
    logical decoding. Each level includes the information logged at all lower 
levels. This parameter can only be set at server start.
   
    In minimal level, WAL-logging of some bulk operations can be safely 
skipped, which can make those operations much faster (see Section 14.4.7). 
Operations in which this optimization can
    be applied include:
   
    CREATE TABLE AS                                                        
    CREATE INDEX                                                           
    CLUSTER                                                                
    COPY into tables that were created or truncated in the same transaction
   
    But minimal WAL does not contain enough information to reconstruct the data 
from a base backup and the WAL logs, so replica or higher must be used to 
enable WAL archiving (archive_mode)
    and streaming replication.
   
    In logical level, the same information is logged as with replica, plus 
information needed to allow extracting logical change sets from the WAL. Using 
a level of logical will increase the
    WAL volume, particularly if many tables are configured for REPLICA IDENTITY 
FULL and many UPDATE and DELETE statements are executed.
   
    In releases prior to 9.6, this parameter also allowed the values archive 
and hot_standby. These are still accepted but mapped to replica.








>
> Thanks!
>
>

-- 
Jerry Sievers
Postgres DBA/Development Consulting
e: postgres.consult...@comcast.net
p: 312.241.7800


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