diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index af3d056b9923..2a834d3517f1 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -2875,7 +2875,8 @@ SELECT NOT(ROW(table.*) IS NOT NULL) FROM TABLE; -- detect at least one null in
Extracts the first substring matching POSIX regular expression; see
- .
+ . (Same as
+ substring(string text, pattern text).)
substring('Thomas' from '...$')
@@ -2888,19 +2889,18 @@ SELECT NOT(ROW(table.*) IS NOT NULL) FROM TABLE; -- detect at least one null in
substring ( string text SIMILAR pattern text ESCAPE escape text )
text
-
- substring ( string text FROM pattern text FOR escape text )
- text
-
Extracts the first substring matching SQL regular expression;
- see . The first form has
- been specified since SQL:2003; the second form was only in SQL:1999
- and should be considered obsolete.
+ see . (Same as
+ substring(string text, pattern text, escape text).)
substring('Thomas' similar '%#"o_a#"_' escape '#')
oma
+
+
+ Obsolescence note: SQL:1999 introduced this function with FROM
+ and FOR as the keywords but switched to this in SQL:2003.
@@ -3796,6 +3796,60 @@ SELECT NOT(ROW(table.*) IS NOT NULL) FROM TABLE; -- detect at least one null in
+
+
+
+ substring ( string text, pattern text )
+ text
+
+
+ Extracts the first substring matching POSIX regular expression; see
+ . (Same as
+ substring(string text FROM pattern text).)
+
+
+ substring('Thomas', '...$')
+ mas
+
+
+
+
+
+ substring ( string text, pattern text, escape text)
+ text
+
+
+ Extracts the first substring matching SQL regular expression;
+ see . (Same as
+ substring(string text SIMILAR pattern text ESCAPE escape text).)
+
+
+ substring('Thomas', '%#"o_a#"_', '#')
+ oma
+
+
+
+
+
+
+ substring
+
+ substring ( string text, start integer , count integer )
+ text
+
+
+ Extracts the substring of string starting at
+ the start'th character,
+ and stopping after count characters if that is
+ specified.
+
+
+
+ substring('Thomas', 2, 3)
+ hom
+
+
+
@@ -4849,6 +4903,27 @@ SELECT format('Testing %3$s, %2$s, %s', 'one', 'two', 'three');
\x5678
+
+
+
+
+ substring
+
+ substring ( bytes bytea, start integer , count integer )
+ bytea
+
+
+ Extracts the substring of bytes starting at
+ the start'th byte,
+ and stopping after count bytes if that is
+ specified.
+
+
+ substring('\x1234567890'::bytea, 3, 2)
+ \x5678
+
+
+
@@ -5351,6 +5426,26 @@ cast(-1234 as bytea) \xfffffb2e
+
+
+
+ substring
+
+ substring ( bits bit, start integer , count integer )
+ bit
+
+
+ Extracts the substring of bits starting at
+ the start'th bit,
+ and stopping after count bits if that is
+ specified.
+
+
+ substring(B'110010111111', 3, 2)
+ 00
+
+
+
@@ -5538,8 +5633,8 @@ cast(-44 as bit(12)) 111111010100
-string LIKE pattern ESCAPE escape-character
-string NOT LIKE pattern ESCAPE escape-character
+string LIKE pattern ESCAPE escape
+string NOT LIKE pattern ESCAPE escape
@@ -5711,8 +5806,8 @@ cast(-44 as bit(12)) 111111010100
-string SIMILAR TO pattern ESCAPE escape-character
-string NOT SIMILAR TO pattern ESCAPE escape-character
+string SIMILAR TO pattern ESCAPE escape
+string NOT SIMILAR TO pattern ESCAPE escape
@@ -5846,15 +5941,11 @@ cast(-44 as bit(12)) 111111010100
regular expression pattern. The function can be written according
to standard SQL syntax:
-substring(string similar pattern escape escape-character)
+substring(string SIMILAR pattern ESCAPE escape)
- or using the now obsolete SQL:1999 syntax:
+ It can also written as a plain three-argument function:
-substring(string from pattern for escape-character)
-
- or as a plain three-argument function:
-
-substring(string, pattern, escape-character)
+substring(string, pattern, escape)
As with SIMILAR TO, the
specified pattern must match the entire data string, or else the
@@ -6058,11 +6149,17 @@ substring('foobar' similar '#"o_b#"%' escape '#') NULL
- The substring function with two parameters,
- substring(string from
- pattern), provides extraction of a
- substring
- that matches a POSIX regular expression pattern. It returns null if
+ The substring function with two parameters provides extraction of a
+ substring that matches a POSIX regular expression pattern.
+ The function can be written according to standard SQL syntax:
+
+substring(string FROM pattern)
+
+ It can also written as a plain two-argument function:
+
+substring(string, pattern)
+
+ It returns null if
there is no match, otherwise the first portion of the text that matched the
pattern. But if the pattern contains any parentheses, the portion
of the text that matched the first parenthesized subexpression (the
diff --git a/src/backend/catalog/system_functions.sql b/src/backend/catalog/system_functions.sql
index 566f308e4439..544b549ae74d 100644
--- a/src/backend/catalog/system_functions.sql
+++ b/src/backend/catalog/system_functions.sql
@@ -42,7 +42,7 @@ CREATE OR REPLACE FUNCTION rpad(text, integer)
IMMUTABLE PARALLEL SAFE STRICT COST 1
RETURN rpad($1, $2, ' ');
-CREATE OR REPLACE FUNCTION "substring"(text, text, text)
+CREATE OR REPLACE FUNCTION "substring"(string text, pattern text, escape text)
RETURNS text
LANGUAGE sql
IMMUTABLE PARALLEL SAFE STRICT COST 1
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 62beb71da288..65e79c0bb41f 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -3705,6 +3705,7 @@
prosrc => 'rtrim' },
{ oid => '877', descr => 'extract portion of string',
proname => 'substr', prorettype => 'text', proargtypes => 'text int4 int4',
+ proargnames => '{string, start, count}',
prosrc => 'text_substr' },
{ oid => '878', descr => 'map a set of characters appearing in string',
proname => 'translate', prorettype => 'text', proargtypes => 'text text text',
@@ -3723,6 +3724,7 @@
prosrc => 'rtrim1' },
{ oid => '883', descr => 'extract portion of string',
proname => 'substr', prorettype => 'text', proargtypes => 'text int4',
+ proargnames => '{string, start}',
prosrc => 'text_substr_no_len' },
{ oid => '884', descr => 'trim selected characters from both ends of string',
proname => 'btrim', prorettype => 'text', proargtypes => 'text text',
@@ -3733,9 +3735,11 @@
{ oid => '936', descr => 'extract portion of string',
proname => 'substring', prorettype => 'text', proargtypes => 'text int4 int4',
+ proargnames => '{string, start, count}',
prosrc => 'text_substr' },
{ oid => '937', descr => 'extract portion of string',
proname => 'substring', prorettype => 'text', proargtypes => 'text int4',
+ proargnames => '{string, start}',
prosrc => 'text_substr_no_len' },
{ oid => '2087',
descr => 'replace all occurrences in string of old_substr with new_substr',
@@ -4153,6 +4157,7 @@
prosrc => 'bitcat' },
{ oid => '1680', descr => 'extract portion of bitstring',
proname => 'substring', prorettype => 'bit', proargtypes => 'bit int4 int4',
+ proargnames => '{bits, start, count}',
prosrc => 'bitsubstr' },
{ oid => '1681', descr => 'bitstring length',
proname => 'length', prorettype => 'int4', proargtypes => 'bit',
@@ -4182,6 +4187,7 @@
prosrc => 'bitposition' },
{ oid => '1699', descr => 'extract portion of bitstring',
proname => 'substring', prorettype => 'bit', proargtypes => 'bit int4',
+ proargnames => '{bits, start}',
prosrc => 'bitsubstr_no_len' },
{ oid => '3030', descr => 'substitute portion of bitstring',
@@ -6279,15 +6285,19 @@
prosrc => 'byteacat' },
{ oid => '2012', descr => 'extract portion of string',
proname => 'substring', prorettype => 'bytea',
+ proargnames => '{bytes, start, count}',
proargtypes => 'bytea int4 int4', prosrc => 'bytea_substr' },
{ oid => '2013', descr => 'extract portion of string',
proname => 'substring', prorettype => 'bytea', proargtypes => 'bytea int4',
+ proargnames => '{bytes, start}',
prosrc => 'bytea_substr_no_len' },
{ oid => '2085', descr => 'extract portion of string',
proname => 'substr', prorettype => 'bytea', proargtypes => 'bytea int4 int4',
+ proargnames => '{bytes, start, count}',
prosrc => 'bytea_substr' },
{ oid => '2086', descr => 'extract portion of string',
proname => 'substr', prorettype => 'bytea', proargtypes => 'bytea int4',
+ proargnames => '{bytes, start}',
prosrc => 'bytea_substr_no_len' },
{ oid => '2014', descr => 'position of substring',
proname => 'position', prorettype => 'int4', proargtypes => 'bytea bytea',
@@ -6479,9 +6489,12 @@
{ oid => '2073', descr => 'extract text matching regular expression',
proname => 'substring', prorettype => 'text', proargtypes => 'text text',
+ proargnames => '{string, pattern}',
prosrc => 'textregexsubstr' },
{ oid => '2074', descr => 'extract text matching SQL regular expression',
proname => 'substring', prolang => 'sql', prorettype => 'text',
+ proargnames => '{string, pattern, escape_character}',
+ proargnames => '{string, pattern, escape}',
proargtypes => 'text text text', prosrc => 'see system_functions.sql' },
{ oid => '2075', descr => 'convert int8 to bitstring',