Wiki / Configuration Parameters

This controls whether a quote mark can be represented by \' in a string literal. The preferred, SQL-standard way to represent a quote mark is by doubling it ('') but PostgreSQL has historically also accepted \'. However, use of \' creates security risks because in some client character set encodings, there are multibyte characters in which the last byte is numerically equivalent to ASCII \. If client-side code does escaping incorrectly then an SQL-injection attack is possible. This risk can be prevented by making the server reject queries in which a quote mark appears to be escaped by a backslash. The allowed values of backslash_quote are on (allow \' always), off (reject always), and safe_encoding (allow only if client encoding does not allow ASCII \ within a multibyte character). safe_encoding is the default setting. Note that in a standard-conforming string literal, \ just means \ anyway. This parameter only affects the handling of non-standard-conforming literals, including escape string syntax (E'...').

English manual coverage begins with PostgreSQL 7.4. Source history and runtime observations have their own recorded version boundaries.

boot val

safe_encoding

category

Version and Platform Compatibility / Previous PostgreSQL Versions

context

user

documented

true

enumvals

safe_encoding, on, off

extra desc

Unknown

lang

en

max val

Unknown

metadata version

18

min val

Unknown

name

backslash_quote

short desc

Sets whether "\'" is allowed in string literals.

source

pg-settings-source-snapshot

unit

Unknown

vartype

enum