diff -cprN head/doc/src/sgml/func.sgml work/doc/src/sgml/func.sgml *** head/doc/src/sgml/func.sgml Tue Jan 26 11:47:08 2010 --- work/doc/src/sgml/func.sgml Thu Jan 28 09:58:12 2010 *************** *** 1789,1794 **** --- 1789,1798 ---- + + See also about the aggregate + function string_agg. + Built-in Conversions *************** SELECT NULLIF(value, '(none)') ... *** 9837,9842 **** --- 9841,9863 ---- + + + string_agg + + string_agg(expression + [, expression ] ) + + + text + + + text + + input values concatenated into an string, optionally separated by the second argument + + + sum(expression) smallint, int, diff -cprN head/src/backend/utils/adt/varlena.c work/src/backend/utils/adt/varlena.c *** head/src/backend/utils/adt/varlena.c Tue Jan 26 11:47:08 2010 --- work/src/backend/utils/adt/varlena.c Thu Jan 28 11:29:55 2010 *************** *** 18,26 **** --- 18,28 ---- #include "access/tuptoaster.h" #include "catalog/pg_type.h" + #include "lib/stringinfo.h" #include "libpq/md5.h" #include "libpq/pqformat.h" #include "miscadmin.h" + #include "nodes/execnodes.h" #include "parser/scansup.h" #include "regex/regex.h" #include "utils/builtins.h" *************** static bytea *bytea_substring(Datum str, *** 73,78 **** --- 75,81 ---- int L, bool length_not_specified); static bytea *bytea_overlay(bytea *t1, bytea *t2, int sp, int sl); + static StringInfo makeStringAggState(fmNodePtr context); /***************************************************************************** *************** pg_column_size(PG_FUNCTION_ARGS) *** 3315,3317 **** --- 3318,3434 ---- PG_RETURN_INT32(result); } + + /* + * string_agg + * + * Concates values and returns string. + * + * Syntax: + * FUNCTION string_agg(string text, delimiter text = '') + * RETURNS text; + * + * Note: any NULL value is ignored. + */ + static StringInfo + makeStringAggState(fmNodePtr context) + { + StringInfo state; + MemoryContext aggcontext; + MemoryContext oldcontext; + + if (context && IsA(context, AggState)) + aggcontext = ((AggState *) context)->aggcontext; + else if (context && IsA(context, WindowAggState)) + aggcontext = ((WindowAggState *) context)->wincontext; + else + { + /* cannot be called directly because of internal-type argument */ + elog(ERROR, "string_agg_transfn called in non-aggregate context"); + aggcontext = NULL; /* keep compiler quiet */ + } + + /* Create state in aggregate context */ + oldcontext = MemoryContextSwitchTo(aggcontext); + state = makeStringInfo(); + MemoryContextSwitchTo(oldcontext); + + return state; + } + + Datum + string_agg1_transfn(PG_FUNCTION_ARGS) + { + StringInfo state; + + state = PG_ARGISNULL(0) ? NULL : (StringInfo) PG_GETARG_POINTER(0); + + /* Append the element only when it isn't null */ + if (!PG_ARGISNULL(1)) + { + text *elem = PG_GETARG_TEXT_PP(1); + + if (state == NULL) + state = makeStringAggState(fcinfo->context); + appendBinaryStringInfo(state, VARDATA_ANY(elem), + VARSIZE_ANY_EXHDR(elem)); + } + + /* + * The transition type for string_agg() is declared to be "internal", which + * is a pass-by-value type the same size as a pointer. + */ + PG_RETURN_POINTER(state); + } + + Datum + string_agg2_transfn(PG_FUNCTION_ARGS) + { + StringInfo state; + + state = PG_ARGISNULL(0) ? NULL : (StringInfo) PG_GETARG_POINTER(0); + + /* Append the element only when it isn't null */ + if (!PG_ARGISNULL(1)) + { + text *elem = PG_GETARG_TEXT_PP(1); + + if (state == NULL) + state = makeStringAggState(fcinfo->context); + else if (!PG_ARGISNULL(2)) + { + text *delim = PG_GETARG_TEXT_PP(2); + appendBinaryStringInfo(state, VARDATA_ANY(delim), + VARSIZE_ANY_EXHDR(delim)); + } + + appendBinaryStringInfo(state, VARDATA_ANY(elem), + VARSIZE_ANY_EXHDR(elem)); + } + + /* + * The transition type for string_agg() is declared to be "internal", which + * is a pass-by-value type the same size as a pointer. + */ + PG_RETURN_POINTER(state); + } + + Datum + string_agg_finalfn(PG_FUNCTION_ARGS) + { + StringInfo state; + + if (PG_ARGISNULL(0)) + PG_RETURN_NULL(); + + /* cannot be called directly because of internal-type argument */ + Assert(fcinfo->context && + (IsA(fcinfo->context, AggState) || + IsA(fcinfo->context, WindowAggState))); + + state = (StringInfo) PG_GETARG_POINTER(0); + if (state != NULL) + PG_RETURN_TEXT_P(cstring_to_text(state->data)); + else + PG_RETURN_NULL(); + } diff -cprN head/src/include/catalog/pg_aggregate.h work/src/include/catalog/pg_aggregate.h *** head/src/include/catalog/pg_aggregate.h Tue Jan 5 10:25:20 2010 --- work/src/include/catalog/pg_aggregate.h Thu Jan 28 09:58:12 2010 *************** DATA(insert ( 2901 xmlconcat2 - 0 *** 223,228 **** --- 223,232 ---- /* array */ DATA(insert ( 2335 array_agg_transfn array_agg_finalfn 0 2281 _null_ )); + /* text */ + DATA(insert (3537 string_agg1_transfn string_agg_finalfn 0 2281 _null_ )); + DATA(insert (3538 string_agg2_transfn string_agg_finalfn 0 2281 _null_ )); + /* * prototypes for functions in pg_aggregate.c */ diff -cprN head/src/include/catalog/pg_proc.h work/src/include/catalog/pg_proc.h *** head/src/include/catalog/pg_proc.h Tue Jan 26 11:47:08 2010 --- work/src/include/catalog/pg_proc.h Thu Jan 28 09:58:12 2010 *************** DESCR("COVAR_SAMP(double, double) aggreg *** 2830,2835 **** --- 2830,2846 ---- DATA(insert OID = 2817 ( float8_corr PGNSP PGUID 12 1 0 0 f f f t f i 1 0 701 "1022" _null_ _null_ _null_ _null_ float8_corr _null_ _null_ _null_ )); DESCR("CORR(double, double) aggregate final function"); + DATA(insert OID = 3534 ( string_agg1_transfn PGNSP PGUID 12 1 0 0 f f f f f i 2 0 2281 "2281 25" _null_ _null_ _null_ _null_ string_agg1_transfn _null_ _null_ _null_ )); + DESCR("string_agg one param transition function"); + DATA(insert OID = 3535 ( string_agg2_transfn PGNSP PGUID 12 1 0 0 f f f f f i 3 0 2281 "2281 25 25" _null_ _null_ _null_ _null_ string_agg2_transfn _null_ _null_ _null_ )); + DESCR("string_agg two params transition function"); + DATA(insert OID = 3536 ( string_agg_finalfn PGNSP PGUID 12 1 0 0 f f f f f i 1 0 25 "2281" _null_ _null_ _null_ _null_ string_agg_finalfn _null_ _null_ _null_ )); + DESCR("string_agg final function"); + DATA(insert OID = 3537 ( string_agg PGNSP PGUID 12 1 0 0 t f f f f i 1 0 25 "25" _null_ _null_ _null_ _null_ aggregate_dummy _null_ _null_ _null_ )); + DESCR("concatenate aggregate input into an string"); + DATA(insert OID = 3538 ( string_agg PGNSP PGUID 12 1 0 0 t f f f f i 2 0 25 "25 25" _null_ _null_ _null_ _null_ aggregate_dummy _null_ _null_ _null_ )); + DESCR("concatenate aggregate input into an string with delimiter"); + /* To ASCII conversion */ DATA(insert OID = 1845 ( to_ascii PGNSP PGUID 12 1 0 0 f f f t f i 1 0 25 "25" _null_ _null_ _null_ _null_ to_ascii_default _null_ _null_ _null_ )); DESCR("encode text from DB encoding to ASCII text"); diff -cprN head/src/include/utils/builtins.h work/src/include/utils/builtins.h *** head/src/include/utils/builtins.h Tue Jan 26 11:47:08 2010 --- work/src/include/utils/builtins.h Thu Jan 28 09:58:12 2010 *************** extern Datum unknownsend(PG_FUNCTION_ARG *** 724,729 **** --- 724,733 ---- extern Datum pg_column_size(PG_FUNCTION_ARGS); + extern Datum string_agg1_transfn(PG_FUNCTION_ARGS); + extern Datum string_agg2_transfn(PG_FUNCTION_ARGS); + extern Datum string_agg_finalfn(PG_FUNCTION_ARGS); + /* version.c */ extern Datum pgsql_version(PG_FUNCTION_ARGS); *************** extern Datum translate(PG_FUNCTION_ARGS) *** 772,777 **** --- 776,784 ---- extern Datum chr (PG_FUNCTION_ARGS); extern Datum repeat(PG_FUNCTION_ARGS); extern Datum ascii(PG_FUNCTION_ARGS); + extern Datum string_agg1_transfn(PG_FUNCTION_ARGS); + extern Datum string_agg2_transfn(PG_FUNCTION_ARGS); + extern Datum string_agg_finalfn(PG_FUNCTION_ARGS); /* inet_net_ntop.c */ extern char *inet_net_ntop(int af, const void *src, int bits, diff -cprN head/src/test/regress/expected/aggregates.out work/src/test/regress/expected/aggregates.out *** head/src/test/regress/expected/aggregates.out Wed Dec 16 09:17:22 2009 --- work/src/test/regress/expected/aggregates.out Thu Jan 28 11:41:07 2010 *************** select aggfns(distinct a,a,c order by a, *** 799,801 **** --- 799,838 ---- ERROR: in an aggregate with DISTINCT, ORDER BY expressions must appear in argument list LINE 1: select aggfns(distinct a,a,c order by a,b) ^ + -- string_agg tests + select string_agg(a) from (values('aaaa'),('bbbb'),('cccc')) g(a); + string_agg + -------------- + aaaabbbbcccc + (1 row) + + select string_agg(a,',') from (values('aaaa'),('bbbb'),('cccc')) g(a); + string_agg + ---------------- + aaaa,bbbb,cccc + (1 row) + + select string_agg(a,',') from (values('aaaa'),(null),('bbbb'),('cccc')) g(a); + string_agg + ---------------- + aaaa,bbbb,cccc + (1 row) + + select string_agg(a,',') from (values(null),(null),('bbbb'),('cccc')) g(a); + string_agg + ------------ + bbbb,cccc + (1 row) + + select string_agg(a,',') from (values(null),(null)) g(a); + string_agg + ------------ + + (1 row) + + select string_agg(elem, delim) from (values('A', ','), ('B', '+'), ('C', '*')) t(elem, delim); + string_agg + ------------ + A+B*C + (1 row) + diff -cprN head/src/test/regress/sql/aggregates.sql work/src/test/regress/sql/aggregates.sql *** head/src/test/regress/sql/aggregates.sql Wed Dec 16 09:17:22 2009 --- work/src/test/regress/sql/aggregates.sql Thu Jan 28 11:40:15 2010 *************** select aggfns(distinct a,b,c order by a, *** 355,357 **** --- 355,365 ---- from (values (1,1,'foo')) v(a,b,c), generate_series(1,2) i; select aggfns(distinct a,a,c order by a,b) from (values (1,1,'foo')) v(a,b,c), generate_series(1,2) i; + + -- string_agg tests + select string_agg(a) from (values('aaaa'),('bbbb'),('cccc')) g(a); + select string_agg(a,',') from (values('aaaa'),('bbbb'),('cccc')) g(a); + select string_agg(a,',') from (values('aaaa'),(null),('bbbb'),('cccc')) g(a); + select string_agg(a,',') from (values(null),(null),('bbbb'),('cccc')) g(a); + select string_agg(a,',') from (values(null),(null)) g(a); + select string_agg(elem, delim) from (values('A', ','), ('B', '+'), ('C', '*')) t(elem, delim);