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Postgres FD Implementation
Commit 49b27ab5 authored by Itagaki Takahiro's avatar Itagaki Takahiro
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Add string functions: concat(), concat_ws(), left(), right(), and reverse(). 

Pavel Stehule, reviewed by me.
parent b9defe04
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Showing with 331 additions and 6 deletions
doc/src/sgml/func.sgml
View file @ 49b27ab5
<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.529 2010/08/17 04:37:20 petere Exp $ -->
<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.530 2010/08/24 06:30:43 itagaki Exp $ -->
<chapter id="functions">
<title>Functions and Operators</title>
......@@ -1250,6 +1250,12 @@
<indexterm>
<primary>chr</primary>
</indexterm>
<indexterm>
<primary>concat</primary>
</indexterm>
<indexterm>
<primary>concat_ws</primary>
</indexterm>
<indexterm>
<primary>convert</primary>
</indexterm>
......@@ -1268,6 +1274,9 @@
<indexterm>
<primary>initcap</primary>
</indexterm>
<indexterm>
<primary>left</primary>
</indexterm>
<indexterm>
<primary>lpad</primary>
</indexterm>
......@@ -1295,6 +1304,12 @@
<indexterm>
<primary>replace</primary>
</indexterm>
<indexterm>
<primary>reverse</primary>
</indexterm>
<indexterm>
<primary>right</primary>
</indexterm>
<indexterm>
<primary>rpad</primary>
</indexterm>
......@@ -1374,6 +1389,34 @@
<entry><literal>A</literal></entry>
</row>
<row>
<entry>
<literal><function>concat</function>(<parameter>str</parameter> <type>"any"</type>
[, <parameter>str</parameter> <type>"any"</type> [, ...] ])</literal>
</entry>
<entry><type>text</type></entry>
<entry>
Concatenate all arguments. NULL arguments are ignored.
</entry>
<entry><literal>concat('abcde', 2, NULL, 22)</literal></entry>
<entry><literal>abcde222</literal></entry>
</row>
<row>
<entry>
<literal><function>concat_ws</function>(<parameter>sep</parameter> <type>text</type>,
<parameter>str</parameter> <type>"any"</type>
[, <parameter>str</parameter> <type>"any"</type> [, ...] ])</literal>
</entry>
<entry><type>text</type></entry>
<entry>
Concatenate all but first arguments with separators. The first
parameter is used as a separator. NULL arguments are ignored.
</entry>
<entry><literal>concat_ws(',', 'abcde', 2, NULL, 22)</literal></entry>
<entry><literal>abcde,2,22</literal></entry>
</row>
<row>
<entry>
<literal><function>convert</function>(<parameter>string</parameter> <type>bytea</type>,
......@@ -1465,6 +1508,20 @@
<entry><literal>Hi Thomas</literal></entry>
</row>
<row>
<entry>
<literal><function>left</function>(<parameter>str</parameter> <type>text</type>,
<parameter>n</parameter> <type>int</type>)</literal>
</entry>
<entry><type>text</type></entry>
<entry>
Return first <replaceable>n</> characters in the string. When <replaceable>n</>
is negative, return all but last |<replaceable>n</>| characters.
</entry>
<entry><literal>left('abcde', 2)</literal></entry>
<entry><literal>ab</literal></entry>
</row>
<row>
<entry><literal><function>length</function>(<parameter>string</parameter>)</literal></entry>
<entry><type>int</type></entry>
......@@ -1678,6 +1735,32 @@
<entry><literal>abXXefabXXef</literal></entry>
</row>
<row>
<entry>
<literal><function>reverse</function>(<parameter>str</parameter>)</literal>
</entry>
<entry><type>text</type></entry>
<entry>
Return reversed string.
</entry>
<entry><literal>reverse('abcde')</literal></entry>
<entry><literal>edcba</literal></entry>
</row>
<row>
<entry>
<literal><function>right</function>(<parameter>str</parameter> <type>text</type>,
<parameter>n</parameter> <type>int</type>)</literal>
</entry>
<entry><type>text</type></entry>
<entry>
Return last <replaceable>n</> characters in the string. When <replaceable>n</>
is negative, return all but first |<replaceable>n</>| characters.
</entry>
<entry><literal>right('abcde', 2)</literal></entry>
<entry><literal>de</literal></entry>
</row>
<row>
<entry>
<literal><function>rpad</function>(<parameter>string</parameter> <type>text</type>,
......
src/backend/utils/adt/varlena.c
View file @ 49b27ab5
......@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/adt/varlena.c,v 1.179 2010/08/10 21:51:00 tgl Exp $
* $PostgreSQL: pgsql/src/backend/utils/adt/varlena.c,v 1.180 2010/08/24 06:30:43 itagaki Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -3556,3 +3556,149 @@ string_agg_finalfn(PG_FUNCTION_ARGS)
else
PG_RETURN_NULL();
}
static text *
concat_internal(const char *sepstr, int seplen, int argidx, FunctionCallInfo fcinfo)
{
StringInfoData str;
text *result;
int i;
initStringInfo(&str);
for (i = argidx; i < PG_NARGS(); i++)
{
if (!PG_ARGISNULL(i))
{
Oid valtype;
Datum value;
Oid typOutput;
bool typIsVarlena;
if (i > argidx)
appendBinaryStringInfo(&str, sepstr, seplen);
/* append n-th value */
value = PG_GETARG_DATUM(i);
valtype = get_fn_expr_argtype(fcinfo->flinfo, i);
getTypeOutputInfo(valtype, &typOutput, &typIsVarlena);
appendStringInfoString(&str,
OidOutputFunctionCall(typOutput, value));
}
}
result = cstring_to_text_with_len(str.data, str.len);
pfree(str.data);
return result;
}
/*
* Concatenate all arguments. NULL arguments are ignored.
*/
Datum
text_concat(PG_FUNCTION_ARGS)
{
PG_RETURN_TEXT_P(concat_internal(NULL, 0, 0, fcinfo));
}
/*
* Concatenate all but first argument values with separators. The first
* parameter is used as a separator. NULL arguments are ignored.
*/
Datum
text_concat_ws(PG_FUNCTION_ARGS)
{
text *sep;
/* return NULL when separator is NULL */
if (PG_ARGISNULL(0))
PG_RETURN_NULL();
sep = PG_GETARG_TEXT_PP(0);
PG_RETURN_TEXT_P(concat_internal(
VARDATA_ANY(sep), VARSIZE_ANY_EXHDR(sep), 1, fcinfo));
}
/*
* Return first n characters in the string. When n is negative,
* return all but last |n| characters.
*/
Datum
text_left(PG_FUNCTION_ARGS)
{
text *str = PG_GETARG_TEXT_PP(0);
const char *p = VARDATA_ANY(str);
int len = VARSIZE_ANY_EXHDR(str);
int n = PG_GETARG_INT32(1);
int rlen;
if (n < 0)
n = pg_mbstrlen_with_len(p, len) + n;
rlen = pg_mbcharcliplen(p, len, n);
PG_RETURN_TEXT_P(cstring_to_text_with_len(p, rlen));
}
/*
* Return last n characters in the string. When n is negative,
* return all but first |n| characters.
*/
Datum
text_right(PG_FUNCTION_ARGS)
{
text *str = PG_GETARG_TEXT_PP(0);
const char *p = VARDATA_ANY(str);
int len = VARSIZE_ANY_EXHDR(str);
int n = PG_GETARG_INT32(1);
int off;
if (n < 0)
n = -n;
else
n = pg_mbstrlen_with_len(p, len) - n;
off = pg_mbcharcliplen(p, len, n);
PG_RETURN_TEXT_P(cstring_to_text_with_len(p + off, len - off));
}
/*
* Return reversed string
*/
Datum
text_reverse(PG_FUNCTION_ARGS)
{
text *str = PG_GETARG_TEXT_PP(0);
const char *p = VARDATA_ANY(str);
int len = VARSIZE_ANY_EXHDR(str);
const char *endp = p + len;
text *result;
char *dst;
result = palloc(len + VARHDRSZ);
dst = (char*) VARDATA(result) + len;
SET_VARSIZE(result, len + VARHDRSZ);
if (pg_database_encoding_max_length() > 1)
{
/* multibyte version */
while (p < endp)
{
int sz;
sz = pg_mblen(p);
dst -= sz;
memcpy(dst, p, sz);
p += sz;
}
}
else
{
/* single byte version */
while (p < endp)
*(--dst) = *p++;
}
PG_RETURN_TEXT_P(result);
}
src/include/catalog/catversion.h
View file @ 49b27ab5
......@@ -37,7 +37,7 @@
* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.596 2010/08/21 10:59:17 mha Exp $
* $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.597 2010/08/24 06:30:43 itagaki Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -53,6 +53,6 @@
*/
/* yyyymmddN */
#define CATALOG_VERSION_NO 201008211
#define CATALOG_VERSION_NO 201008241
#endif
src/include/catalog/pg_proc.h
View file @ 49b27ab5
......@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.580 2010/08/21 10:59:17 mha Exp $
* $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.581 2010/08/24 06:30:43 itagaki Exp $
*
* NOTES
* The script catalog/genbki.pl reads this file and generates .bki
......@@ -2722,6 +2722,16 @@ DESCR("I/O");
DATA(insert OID = 1799 ( oidout PGNSP PGUID 12 1 0 0 f f f t f i 1 0 2275 "26" _null_ _null_ _null_ _null_ oidout _null_ _null_ _null_ ));
DESCR("I/O");
DATA(insert OID = 3058 ( concat PGNSP PGUID 12 1 0 2276 f f f f f s 1 0 25 "2276" "{2276}" "{v}" _null_ _null_ text_concat _null_ _null_ _null_ ));
DESCR("concatenate values");
DATA(insert OID = 3059 ( concat_ws PGNSP PGUID 12 1 0 2276 f f f f f s 2 0 25 "25 2276" "{25,2276}" "{i,v}" _null_ _null_ text_concat_ws _null_ _null_ _null_ ));
DESCR("concatenate values with separators");
DATA(insert OID = 3060 ( left PGNSP PGUID 12 1 0 0 f f f t f i 2 0 25 "25 23" _null_ _null_ _null_ _null_ text_left _null_ _null_ _null_ ));
DESCR("return the first n characters");
DATA(insert OID = 3061 ( right PGNSP PGUID 12 1 0 0 f f f t f i 2 0 25 "25 23" _null_ _null_ _null_ _null_ text_right _null_ _null_ _null_ ));
DESCR("return the last n characters");
DATA(insert OID = 3062 ( reverse PGNSP PGUID 12 1 0 0 f f f t f i 1 0 25 "25" _null_ _null_ _null_ _null_ text_reverse _null_ _null_ _null_ ));
DESCR("reverse text");
DATA(insert OID = 1810 ( bit_length PGNSP PGUID 14 1 0 0 f f f t f i 1 0 23 "17" _null_ _null_ _null_ _null_ "select pg_catalog.octet_length($1) * 8" _null_ _null_ _null_ ));
DESCR("length in bits");
......
src/include/utils/builtins.h
View file @ 49b27ab5
......@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/utils/builtins.h,v 1.354 2010/08/10 21:51:00 tgl Exp $
* $PostgreSQL: pgsql/src/include/utils/builtins.h,v 1.355 2010/08/24 06:30:44 itagaki Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -733,6 +733,12 @@ extern Datum pg_column_size(PG_FUNCTION_ARGS);
extern Datum string_agg_transfn(PG_FUNCTION_ARGS);
extern Datum string_agg_finalfn(PG_FUNCTION_ARGS);
extern Datum text_concat(PG_FUNCTION_ARGS);
extern Datum text_concat_ws(PG_FUNCTION_ARGS);
extern Datum text_left(PG_FUNCTION_ARGS);
extern Datum text_right(PG_FUNCTION_ARGS);
extern Datum text_reverse(PG_FUNCTION_ARGS);
/* version.c */
extern Datum pgsql_version(PG_FUNCTION_ARGS);
......
src/test/regress/expected/text.out
View file @ 49b27ab5
......@@ -51,3 +51,70 @@ ERROR: operator does not exist: integer || numeric
LINE 1: select 3 || 4.0;
^
HINT: No operator matches the given name and argument type(s). You might need to add explicit type casts.
/*
* string functions
*/
select concat('one');
concat
--------
one
(1 row)
select concat(1,2,3,'hello',true, false, to_date('20100309','YYYYMMDD'));
concat
----------------------
123hellotf03-09-2010
(1 row)
select concat_ws('#','one');
concat_ws
-----------
one
(1 row)
select concat_ws('#',1,2,3,'hello',true, false, to_date('20100309','YYYYMMDD'));
concat_ws
----------------------------
1#2#3#hello#t#f#03-09-2010
(1 row)
select concat_ws(',',10,20,null,30);
concat_ws
-----------
10,20,30
(1 row)
select concat_ws('',10,20,null,30);
concat_ws
-----------
102030
(1 row)
select concat_ws(NULL,10,20,null,30) is null;
?column?
----------
t
(1 row)
select reverse('abcde');
reverse
---------
edcba
(1 row)
select i, left('ahoj', i), right('ahoj', i) from generate_series(-5, 5) t(i) order by i;
i | left | right
----+------+-------
-5 | |
-4 | |
-3 | a | j
-2 | ah | oj
-1 | aho | hoj
0 | |
1 | a | j
2 | ah | oj
3 | aho | hoj
4 | ahoj | ahoj
5 | ahoj | ahoj
(11 rows)
src/test/regress/sql/text.sql
View file @ 49b27ab5
......@@ -28,3 +28,16 @@ select 'four: ' || 2+2;
-- but not this:
select 3 || 4.0;
/*
* string functions
*/
select concat('one');
select concat(1,2,3,'hello',true, false, to_date('20100309','YYYYMMDD'));
select concat_ws('#','one');
select concat_ws('#',1,2,3,'hello',true, false, to_date('20100309','YYYYMMDD'));
select concat_ws(',',10,20,null,30);
select concat_ws('',10,20,null,30);
select concat_ws(NULL,10,20,null,30) is null;
select reverse('abcde');
select i, left('ahoj', i), right('ahoj', i) from generate_series(-5, 5) t(i) order by i;
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