Hi with array_offsets - returns a array of offsets
Regards Pavel 2015-01-20 21:32 GMT+01:00 Jim Nasby <jim.na...@bluetreble.com>: > On 1/20/15 11:12 AM, Pavel Stehule wrote: > >> I am sending updated version - it allow third optional argument that >> specify where searching should to start. With it is possible repeatably >> call this function. >> > > What happened to returning an array of offsets? I think that would be both > easier to use than this version as well as performing better. > > I see you dropped multi-dimension support, but I think that's fine. > > -- > Jim Nasby, Data Architect, Blue Treble Consulting > Data in Trouble? Get it in Treble! http://BlueTreble.com >
diff --git a/doc/src/sgml/array.sgml b/doc/src/sgml/array.sgml new file mode 100644 index 9ea1068..b3630b4 *** a/doc/src/sgml/array.sgml --- b/doc/src/sgml/array.sgml *************** SELECT * FROM sal_emp WHERE pay_by_quart *** 600,605 **** --- 600,614 ---- index, as described in <xref linkend="indexes-types">. </para> + <para> + You can also search any value in array using the <function>array_offset</> + function (It returns a position of first occurrence of value in the array): + + <programlisting> + SELECT array_offset(ARRAY['sun','mon','tue','wen','thu','fri','sat'], 'mon'); + </programlisting> + </para> + <tip> <para> Arrays are not sets; searching for specific array elements diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml new file mode 100644 index d57243a..c563165 *** a/doc/src/sgml/func.sgml --- b/doc/src/sgml/func.sgml *************** SELECT NULLIF(value, '(none)') ... *** 11474,11479 **** --- 11474,11482 ---- <primary>array_lower</primary> </indexterm> <indexterm> + <primary>array_offset</primary> + </indexterm> + <indexterm> <primary>array_prepend</primary> </indexterm> <indexterm> *************** SELECT NULLIF(value, '(none)') ... *** 11592,11597 **** --- 11595,11626 ---- </row> <row> <entry> + <literal> + <function>array_offset</function>(<type>anyarray</type>, <type>anyelement</type> <optional>, <type>int</type></optional>) + </literal> + </entry> + <entry><type>int</type></entry> + <entry>returns a offset of first occurrence of some element in a array. It uses + a <literal>IS NOT DISTINCT FROM</> operator for comparation. Third + optional argument can specify a initial offset when searching starts. </entry> + <entry><literal>array_offset(ARRAY['sun','mon','tue','wen','thu','fri','sat'], 'mon')</literal></entry> + <entry><literal>2</literal></entry> + </row> + <row> + <entry> + <literal> + <function>array_offsets</function>(<type>anyarray</type>, <type>anyelement</type>) + </literal> + </entry> + <entry><type>int[]</type></entry> + <entry>returns a array of offset of all occurrences some element in a array. It uses + a <literal>IS NOT DISTINCT FROM</> operator for comparation. Returns empty array, + when there are no occurence of element in input array.</entry> + <entry><literal>array_offsets(ARRAY['A','A','B','A'], 'A')</literal></entry> + <entry><literal>{1,2,4}</literal></entry> + </row> + <row> + <entry> <literal> <function>array_prepend</function>(<type>anyelement</type>, <type>anyarray</type>) </literal> diff --git a/src/backend/utils/adt/array_userfuncs.c b/src/backend/utils/adt/array_userfuncs.c new file mode 100644 index 600646e..61a080d *** a/src/backend/utils/adt/array_userfuncs.c --- b/src/backend/utils/adt/array_userfuncs.c *************** *** 12,20 **** --- 12,24 ---- */ #include "postgres.h" + #include "catalog/pg_type.h" #include "utils/array.h" #include "utils/builtins.h" #include "utils/lsyscache.h" + #include "utils/typcache.h" + + static bool array_offset_common(FunctionCallInfo fcinfo, int *result); /*----------------------------------------------------------------------------- *************** array_agg_array_finalfn(PG_FUNCTION_ARGS *** 612,614 **** --- 616,879 ---- PG_RETURN_DATUM(result); } + + + /* + * array_offset - returns a offset of entered element in a array. + * Returns NULL when values is not a element of the array. It allow + * searching a NULL value due using a NOT DISTINCT FROM operator. + * + * Biggest difference against width_array is unsorted input array. + */ + Datum + array_offset(PG_FUNCTION_ARGS) + { + int result; + + if (array_offset_common(fcinfo, &result)) + PG_RETURN_INT32(result); + + PG_RETURN_NULL(); + } + + + Datum + array_offset_start(PG_FUNCTION_ARGS) + { + int result; + + if (array_offset_common(fcinfo, &result)) + PG_RETURN_INT32(result); + + PG_RETURN_NULL(); + } + + /* + * Common part for functions array_offset and array_offset_startpos + */ + static bool + array_offset_common(FunctionCallInfo fcinfo, + int *result) + { + ArrayType *array; + Oid collation = PG_GET_COLLATION(); + Oid element_type; + Datum searched_element = (Datum) 0, + value; + bool isnull; + int offset = 0, + offset_min = 1; + bool found = false; + TypeCacheEntry *typentry; + ArrayMetaState *my_extra; + bool null_search; + ArrayIterator array_iterator; + + if (PG_ARGISNULL(0)) + return false; + + array = PG_GETARG_ARRAYTYPE_P(0); + element_type = ARR_ELEMTYPE(array); + + if (PG_ARGISNULL(1)) + { + if (!array_contains_nulls(array)) + return false; + null_search = true; + } + else + { + searched_element = PG_GETARG_DATUM(1); + null_search = false; + } + + if (PG_NARGS() == 3) + { + if (PG_ARGISNULL(2)) + ereport(ERROR, + (errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED), + errmsg("initial offset should not be NULL"))); + + offset_min = PG_GETARG_INT32(2); + } + + /* cache operator info */ + my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra; + if (my_extra == NULL) + { + fcinfo->flinfo->fn_extra = MemoryContextAlloc(fcinfo->flinfo->fn_mcxt, + sizeof(ArrayMetaState)); + my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra; + my_extra->element_type = ~element_type; + } + + if (my_extra->element_type != element_type) + { + get_typlenbyvalalign(element_type, + &my_extra->typlen, + &my_extra->typbyval, + &my_extra->typalign); + + typentry = lookup_type_cache(element_type, + TYPECACHE_EQ_OPR_FINFO); + + if (!OidIsValid(typentry->eq_opr_finfo.fn_oid)) + ereport(ERROR, + (errcode(ERRCODE_UNDEFINED_FUNCTION), + errmsg("could not identify an equality operator for type %s", + format_type_be(element_type)))); + + my_extra->element_type = element_type; + fmgr_info(typentry->eq_opr_finfo.fn_oid, &my_extra->proc); + } + + array_iterator = array_create_iterator(array, 0, my_extra); + + while (array_iterate(array_iterator, &value, &isnull)) + { + offset += 1; + + if (offset < offset_min) + continue; + + if (isnull || null_search) + { + + if (isnull && null_search) + { + found = true; + break; + } + else + continue; + } + + if (DatumGetBool(FunctionCall2Coll(&my_extra->proc, collation, + searched_element, + value))) + { + found = true; + break; + } + } + + array_free_iterator(array_iterator); + + /* Avoid leaking memory when handed toasted input */ + PG_FREE_IF_COPY(array, 0); + + if (!found) + return false; + + *result = offset; + + return true; + } + + /* + * Returns a array of offsets of some value in array. + * Returns NULL, the array is NULL. When searching doesn't produce + * any value, then it returns empty array. + */ + Datum + array_offsets(PG_FUNCTION_ARGS) + { + ArrayType *array; + Oid collation = PG_GET_COLLATION(); + Oid element_type; + Datum searched_element = (Datum) 0, + value; + bool isnull; + int offset = 0; + TypeCacheEntry *typentry; + ArrayMetaState *my_extra; + bool null_search; + ArrayIterator array_iterator; + ArrayBuildState *astate = NULL; + + if (PG_ARGISNULL(0)) + PG_RETURN_NULL(); + + array = PG_GETARG_ARRAYTYPE_P(0); + element_type = ARR_ELEMTYPE(array); + + astate = initArrayResult(INT4OID, CurrentMemoryContext); + + if (PG_ARGISNULL(1)) + { + /* fast return when we have no NULL */ + if (!array_contains_nulls(array)) + PG_RETURN_DATUM(makeArrayResult(astate, CurrentMemoryContext)); + + null_search = true; + } + else + { + searched_element = PG_GETARG_DATUM(1); + null_search = false; + } + + element_type = ARR_ELEMTYPE(array); + + /* cache operator info */ + my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra; + if (my_extra == NULL) + { + fcinfo->flinfo->fn_extra = MemoryContextAlloc(fcinfo->flinfo->fn_mcxt, + sizeof(ArrayMetaState)); + my_extra = (ArrayMetaState *) fcinfo->flinfo->fn_extra; + my_extra->element_type = ~element_type; + } + + if (my_extra->element_type != element_type) + { + get_typlenbyvalalign(element_type, + &my_extra->typlen, + &my_extra->typbyval, + &my_extra->typalign); + + typentry = lookup_type_cache(element_type, + TYPECACHE_EQ_OPR_FINFO); + + if (!OidIsValid(typentry->eq_opr_finfo.fn_oid)) + ereport(ERROR, + (errcode(ERRCODE_UNDEFINED_FUNCTION), + errmsg("could not identify an equality operator for type %s", + format_type_be(element_type)))); + + my_extra->element_type = element_type; + fmgr_info(typentry->eq_opr_finfo.fn_oid, &my_extra->proc); + } + + array_iterator = array_create_iterator(array, 0, my_extra); + + while (array_iterate(array_iterator, &value, &isnull)) + { + offset += 1; + + if (isnull || null_search) + { + + if (isnull && null_search) + astate = accumArrayResult(astate, + Int32GetDatum(offset), false, INT4OID, + CurrentMemoryContext); + + continue; + } + + if (DatumGetBool(FunctionCall2Coll(&my_extra->proc, collation, + searched_element, + value))) + astate = accumArrayResult(astate, + Int32GetDatum(offset), false, INT4OID, + CurrentMemoryContext); + } + + array_free_iterator(array_iterator); + + /* Avoid leaking memory when handed toasted input */ + PG_FREE_IF_COPY(array, 0); + + PG_RETURN_DATUM(makeArrayResult(astate, CurrentMemoryContext)); + } diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c new file mode 100644 index 5591b46..9ab1da0 *** a/src/backend/utils/adt/arrayfuncs.c --- b/src/backend/utils/adt/arrayfuncs.c *************** arraycontained(PG_FUNCTION_ARGS) *** 3945,3951 **** * The passed-in array must remain valid for the lifetime of the iterator. */ ArrayIterator ! array_create_iterator(ArrayType *arr, int slice_ndim) { ArrayIterator iterator = palloc0(sizeof(ArrayIteratorData)); --- 3945,3951 ---- * The passed-in array must remain valid for the lifetime of the iterator. */ ArrayIterator ! array_create_iterator(ArrayType *arr, int slice_ndim, ArrayMetaState *mstate) { ArrayIterator iterator = palloc0(sizeof(ArrayIteratorData)); *************** array_create_iterator(ArrayType *arr, in *** 3962,3971 **** iterator->arr = arr; iterator->nullbitmap = ARR_NULLBITMAP(arr); iterator->nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr)); ! get_typlenbyvalalign(ARR_ELEMTYPE(arr), ! &iterator->typlen, ! &iterator->typbyval, ! &iterator->typalign); /* * Remember the slicing parameters. --- 3962,3981 ---- iterator->arr = arr; iterator->nullbitmap = ARR_NULLBITMAP(arr); iterator->nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr)); ! ! if (mstate != NULL) ! { ! Assert(mstate->element_type == ARR_ELEMTYPE(arr)); ! ! iterator->typlen = mstate->typlen; ! iterator->typbyval = mstate->typbyval; ! iterator->typalign = mstate->typalign; ! } ! else ! get_typlenbyvalalign(ARR_ELEMTYPE(arr), ! &iterator->typlen, ! &iterator->typbyval, ! &iterator->typalign); /* * Remember the slicing parameters. diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h new file mode 100644 index 9edfdb8..1358531 *** a/src/include/catalog/pg_proc.h --- b/src/include/catalog/pg_proc.h *************** DATA(insert OID = 515 ( array_larger *** 895,900 **** --- 895,906 ---- DESCR("larger of two"); DATA(insert OID = 516 ( array_smaller PGNSP PGUID 12 1 0 0 0 f f f f t f i 2 0 2277 "2277 2277" _null_ _null_ _null_ _null_ array_smaller _null_ _null_ _null_ )); DESCR("smaller of two"); + DATA(insert OID = 3277 ( array_offset PGNSP PGUID 12 1 0 0 0 f f f f f f i 2 0 23 "2277 2283" _null_ _null_ _null_ _null_ array_offset _null_ _null_ _null_ )); + DESCR("returns a offset of value in array"); + DATA(insert OID = 3278 ( array_offset PGNSP PGUID 12 1 0 0 0 f f f f f f i 3 0 23 "2277 2283 23" _null_ _null_ _null_ _null_ array_offset_start _null_ _null_ _null_ )); + DESCR("returns a offset of value in array with start index"); + DATA(insert OID = 3279 ( array_offsets PGNSP PGUID 12 1 0 0 0 f f f f f f i 2 0 1007 "2277 2283" _null_ _null_ _null_ _null_ array_offsets _null_ _null_ _null_ )); + DESCR("returns a array of offsets of some value in array"); DATA(insert OID = 1191 ( generate_subscripts PGNSP PGUID 12 1 1000 0 0 f f f f t t i 3 0 23 "2277 23 16" _null_ _null_ _null_ _null_ generate_subscripts _null_ _null_ _null_ )); DESCR("array subscripts generator"); DATA(insert OID = 1192 ( generate_subscripts PGNSP PGUID 12 1 1000 0 0 f f f f t t i 2 0 23 "2277 23" _null_ _null_ _null_ _null_ generate_subscripts_nodir _null_ _null_ _null_ )); diff --git a/src/include/utils/array.h b/src/include/utils/array.h new file mode 100644 index 694bce7..aabc792 *** a/src/include/utils/array.h --- b/src/include/utils/array.h *************** extern ArrayBuildStateAny *accumArrayRes *** 314,320 **** extern Datum makeArrayResultAny(ArrayBuildStateAny *astate, MemoryContext rcontext, bool release); ! extern ArrayIterator array_create_iterator(ArrayType *arr, int slice_ndim); extern bool array_iterate(ArrayIterator iterator, Datum *value, bool *isnull); extern void array_free_iterator(ArrayIterator iterator); --- 314,320 ---- extern Datum makeArrayResultAny(ArrayBuildStateAny *astate, MemoryContext rcontext, bool release); ! extern ArrayIterator array_create_iterator(ArrayType *arr, int slice_ndim, ArrayMetaState *mstate); extern bool array_iterate(ArrayIterator iterator, Datum *value, bool *isnull); extern void array_free_iterator(ArrayIterator iterator); *************** extern Datum array_agg_finalfn(PG_FUNCTI *** 348,353 **** --- 348,357 ---- extern Datum array_agg_array_transfn(PG_FUNCTION_ARGS); extern Datum array_agg_array_finalfn(PG_FUNCTION_ARGS); + extern Datum array_offset(PG_FUNCTION_ARGS); + extern Datum array_offset_start(PG_FUNCTION_ARGS); + extern Datum array_offsets(PG_FUNCTION_ARGS); + /* * prototypes for functions defined in array_typanalyze.c */ diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c new file mode 100644 index ae5421f..3d87520 *** a/src/pl/plpgsql/src/pl_exec.c --- b/src/pl/plpgsql/src/pl_exec.c *************** exec_stmt_foreach_a(PLpgSQL_execstate *e *** 2304,2310 **** errmsg("FOREACH loop variable must not be of an array type"))); /* Create an iterator to step through the array */ ! array_iterator = array_create_iterator(arr, stmt->slice); /* Identify iterator result type */ if (stmt->slice > 0) --- 2304,2310 ---- errmsg("FOREACH loop variable must not be of an array type"))); /* Create an iterator to step through the array */ ! array_iterator = array_create_iterator(arr, stmt->slice, NULL); /* Identify iterator result type */ if (stmt->slice > 0) diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out new file mode 100644 index d33c9b9..75fc16a *** a/src/test/regress/expected/arrays.out --- b/src/test/regress/expected/arrays.out *************** SELECT array_cat(ARRAY[[3,4],[5,6]], ARR *** 366,371 **** --- 366,478 ---- {{3,4},{5,6},{1,2}} (1 row) + SELECT array_offset(ARRAY[1,2,3,4,5], 4); + array_offset + -------------- + 4 + (1 row) + + SELECT array_offset(ARRAY[5,3,4,2,1], 4); + array_offset + -------------- + 3 + (1 row) + + SELECT array_offset(ARRAY[[1,2],[3,4]], 3); + array_offset + -------------- + 3 + (1 row) + + SELECT array_offset(ARRAY[[1,2],[3,4]], 4); + array_offset + -------------- + 4 + (1 row) + + SELECT array_offset(ARRAY['sun','mon','tue','wen','thu','fri','sat'], 'mon'); + array_offset + -------------- + 2 + (1 row) + + SELECT array_offset(ARRAY['sun','mon','tue','wen','thu','fri','sat'], 'sat'); + array_offset + -------------- + 7 + (1 row) + + SELECT array_offset(ARRAY['sun','mon','tue','wen','thu','fri','sat'], NULL); + array_offset + -------------- + + (1 row) + + SELECT array_offset(ARRAY['sun','mon','tue','wen','thu',NULL,'fri','sat'], NULL); + array_offset + -------------- + 6 + (1 row) + + SELECT array_offset(ARRAY['sun','mon','tue','wen','thu',NULL,'fri','sat'], 'sat'); + array_offset + -------------- + 8 + (1 row) + + SELECT array_offsets(NULL, 10); + array_offsets + --------------- + + (1 row) + + SELECT array_offsets(NULL, NULL::int); + array_offsets + --------------- + + (1 row) + + SELECT array_offsets(ARRAY[1,2,3,4,5,6,1,2,3,4,5,6], 4); + array_offsets + --------------- + {4,10} + (1 row) + + SELECT array_offsets(ARRAY[1,2,3,4,5,6,1,2,3,4,5,6], NULL); + array_offsets + --------------- + {} + (1 row) + + SELECT array_offsets(ARRAY[1,2,3,NULL,5,6,1,2,3,NULL,5,6], NULL); + array_offsets + --------------- + {4,10} + (1 row) + + SELECT array_length(array_offsets(ARRAY(SELECT 'AAAAAAAAAAAAAAAAAAAAAAAAA'::text || i % 10 FROM generate_series(1,100) g(i)), + 'AAAAAAAAAAAAAAAAAAAAAAAAA5'),1); + array_length + -------------- + 10 + (1 row) + + do $$ + declare + o int; + a int[] := ARRAY[1,2,3,2,3,1,2]; + begin + o := array_offset(a, 2); + while o is not null + loop + raise notice '%', o; + o := array_offset(a, 2, o + 1); + end loop; + end + $$ language plpgsql; + NOTICE: 2 + NOTICE: 4 + NOTICE: 7 -- operators SELECT a FROM arrtest WHERE b = ARRAY[[[113,142],[1,147]]]; a diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql new file mode 100644 index 733c19b..86058a5 *** a/src/test/regress/sql/arrays.sql --- b/src/test/regress/sql/arrays.sql *************** SELECT array_cat(ARRAY[1,2], ARRAY[3,4]) *** 185,190 **** --- 185,222 ---- SELECT array_cat(ARRAY[1,2], ARRAY[[3,4],[5,6]]) AS "{{1,2},{3,4},{5,6}}"; SELECT array_cat(ARRAY[[3,4],[5,6]], ARRAY[1,2]) AS "{{3,4},{5,6},{1,2}}"; + SELECT array_offset(ARRAY[1,2,3,4,5], 4); + SELECT array_offset(ARRAY[5,3,4,2,1], 4); + SELECT array_offset(ARRAY[[1,2],[3,4]], 3); + SELECT array_offset(ARRAY[[1,2],[3,4]], 4); + SELECT array_offset(ARRAY['sun','mon','tue','wen','thu','fri','sat'], 'mon'); + SELECT array_offset(ARRAY['sun','mon','tue','wen','thu','fri','sat'], 'sat'); + SELECT array_offset(ARRAY['sun','mon','tue','wen','thu','fri','sat'], NULL); + SELECT array_offset(ARRAY['sun','mon','tue','wen','thu',NULL,'fri','sat'], NULL); + SELECT array_offset(ARRAY['sun','mon','tue','wen','thu',NULL,'fri','sat'], 'sat'); + + SELECT array_offsets(NULL, 10); + SELECT array_offsets(NULL, NULL::int); + SELECT array_offsets(ARRAY[1,2,3,4,5,6,1,2,3,4,5,6], 4); + SELECT array_offsets(ARRAY[1,2,3,4,5,6,1,2,3,4,5,6], NULL); + SELECT array_offsets(ARRAY[1,2,3,NULL,5,6,1,2,3,NULL,5,6], NULL); + SELECT array_length(array_offsets(ARRAY(SELECT 'AAAAAAAAAAAAAAAAAAAAAAAAA'::text || i % 10 FROM generate_series(1,100) g(i)), + 'AAAAAAAAAAAAAAAAAAAAAAAAA5'),1); + + do $$ + declare + o int; + a int[] := ARRAY[1,2,3,2,3,1,2]; + begin + o := array_offset(a, 2); + while o is not null + loop + raise notice '%', o; + o := array_offset(a, 2, o + 1); + end loop; + end + $$ language plpgsql; + -- operators SELECT a FROM arrtest WHERE b = ARRAY[[[113,142],[1,147]]]; SELECT NOT ARRAY[1.1,1.2,1.3] = ARRAY[1.1,1.2,1.3] AS "FALSE";
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