The view pg_settings provides access to
run-time parameters of the server. It is essentially an alternative
interface to the SHOW and SET commands.
It also provides access to some facts about each parameter that are
not directly available from SHOW, such as minimum and
maximum values.
Table 42-41. pg_settings Columns
Name
Type
References
Description
name
text
run-time configuration parameter name
setting
text
current value of the parameter
category
text
logical group of the parameter
short_desc
text
a brief description of the parameter
extra_desc
text
additional, more detailed, information about the parameter
context
text
context required to set the parameter's value
vartype
text
parameter type (bool, integer,
real, or string)
source
text
source of the current parameter value
min_val
text
minimum allowed value of the parameter (NULL for nonnumeric
values)
max_val
text
maximum allowed value of the parameter (NULL for nonnumeric
values)
The pg_settings view cannot be inserted into or
deleted from, but it can be updated. An UPDATE applied
to a row of pg_settings is equivalent to executing
the SET command on that named
parameter. The change only affects the value used by the current
session. If an UPDATE is issued within a transaction
that is later aborted, the effects of the UPDATE command
disappear when the transaction is rolled back. Once the surrounding
transaction is committed, the effects will persist until the end of the
session, unless overridden by another UPDATE or
SET.