Currently, json_agg, jsonb_agg, json_object_agg and jsonb_object_agg do
type classification on their arguments on each call to the transition
function. This is quite unnecessary, as the argument types won't change.
This patch remedies the defect by caching the necessary values in the
aggregate state object.
While this doesn't change the performance much, since these functions
are essentially dominated by other bits of the processing, I think it is
nevertheless worth doing.
There are other areas where we might attack this, also. In particular,
if one of the arguments is a record, then composite_to_json(b) will do
this for every attribute of every record. However, it's much less clear
to me how we can cache this information sensibly.
cheers
andrew
diff --git a/src/backend/utils/adt/json.c b/src/backend/utils/adt/json.c
index 8d04347..d199421 100644
--- a/src/backend/utils/adt/json.c
+++ b/src/backend/utils/adt/json.c
@@ -68,6 +68,15 @@ typedef enum /* type categories for datum_to_json */
JSONTYPE_OTHER /* all else */
} JsonTypeCategory;
+typedef struct JsonAggState
+{
+ StringInfo str;
+ JsonTypeCategory key_category;
+ Oid key_output_func;
+ JsonTypeCategory val_category;
+ Oid val_output_func;
+} JsonAggState;
+
static inline void json_lex(JsonLexContext *lex);
static inline void json_lex_string(JsonLexContext *lex);
static inline void json_lex_number(JsonLexContext *lex, char *s, bool *num_err);
@@ -1858,18 +1867,10 @@ to_json(PG_FUNCTION_ARGS)
Datum
json_agg_transfn(PG_FUNCTION_ARGS)
{
- Oid val_type = get_fn_expr_argtype(fcinfo->flinfo, 1);
MemoryContext aggcontext,
oldcontext;
- StringInfo state;
+ JsonAggState *state;
Datum val;
- JsonTypeCategory tcategory;
- Oid outfuncoid;
-
- if (val_type == InvalidOid)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
- errmsg("could not determine input data type")));
if (!AggCheckCallContext(fcinfo, &aggcontext))
{
@@ -1879,50 +1880,62 @@ json_agg_transfn(PG_FUNCTION_ARGS)
if (PG_ARGISNULL(0))
{
+ Oid val_type = get_fn_expr_argtype(fcinfo->flinfo, 1);
+ JsonTypeCategory tcategory;
+ Oid outfuncoid;
+
+ if (val_type == InvalidOid)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("could not determine input data type")));
+
/*
- * Make this StringInfo in a context where it will persist for the
+ * Make this state object in a context where it will persist for the
* duration of the aggregate call. MemoryContextSwitchTo is only
* needed the first time, as the StringInfo routines make sure they
* use the right context to enlarge the object if necessary.
*/
oldcontext = MemoryContextSwitchTo(aggcontext);
- state = makeStringInfo();
+ state = (JsonAggState *) palloc(sizeof(JsonAggState));
+ state->str = makeStringInfo();
MemoryContextSwitchTo(oldcontext);
- appendStringInfoChar(state, '[');
+ appendStringInfoChar(state->str, '[');
+ json_categorize_type(val_type,&tcategory, &outfuncoid);
+ state->val_category = tcategory;
+ state->val_output_func = outfuncoid;
}
else
{
- state = (StringInfo) PG_GETARG_POINTER(0);
- appendStringInfoString(state, ", ");
+ state = (JsonAggState *) PG_GETARG_POINTER(0);
+ appendStringInfoString(state->str, ", ");
}
/* fast path for NULLs */
if (PG_ARGISNULL(1))
{
- datum_to_json((Datum) 0, true, state, JSONTYPE_NULL, InvalidOid, false);
+ datum_to_json((Datum) 0, true, state->str, JSONTYPE_NULL,
+ InvalidOid, false);
PG_RETURN_POINTER(state);
}
val = PG_GETARG_DATUM(1);
- /* XXX we do this every time?? */
- json_categorize_type(val_type,
- &tcategory, &outfuncoid);
-
/* add some whitespace if structured type and not first item */
if (!PG_ARGISNULL(0) &&
- (tcategory == JSONTYPE_ARRAY || tcategory == JSONTYPE_COMPOSITE))
+ (state->val_category == JSONTYPE_ARRAY ||
+ state->val_category == JSONTYPE_COMPOSITE))
{
- appendStringInfoString(state, "\n ");
+ appendStringInfoString(state->str, "\n ");
}
- datum_to_json(val, false, state, tcategory, outfuncoid, false);
+ datum_to_json(val, false, state->str, state->val_category,
+ state->val_output_func, false);
/*
* The transition type for array_agg() is declared to be "internal", which
* is a pass-by-value type the same size as a pointer. So we can safely
- * pass the ArrayBuildState pointer through nodeAgg.c's machinations.
+ * pass the JsonAggState pointer through nodeAgg.c's machinations.
*/
PG_RETURN_POINTER(state);
}
@@ -1933,19 +1946,21 @@ json_agg_transfn(PG_FUNCTION_ARGS)
Datum
json_agg_finalfn(PG_FUNCTION_ARGS)
{
- StringInfo state;
+ JsonAggState *state;
/* cannot be called directly because of internal-type argument */
Assert(AggCheckCallContext(fcinfo, NULL));
- state = PG_ARGISNULL(0) ? NULL : (StringInfo) PG_GETARG_POINTER(0);
+ state = PG_ARGISNULL(0) ?
+ NULL :
+ (JsonAggState *) PG_GETARG_POINTER(0);
/* NULL result for no rows in, as is standard with aggregates */
if (state == NULL)
PG_RETURN_NULL();
/* Else return state with appropriate array terminator added */
- PG_RETURN_TEXT_P(catenate_stringinfo_string(state, "]"));
+ PG_RETURN_TEXT_P(catenate_stringinfo_string(state->str, "]"));
}
/*
@@ -1956,10 +1971,9 @@ json_agg_finalfn(PG_FUNCTION_ARGS)
Datum
json_object_agg_transfn(PG_FUNCTION_ARGS)
{
- Oid val_type;
MemoryContext aggcontext,
oldcontext;
- StringInfo state;
+ JsonAggState *state;
Datum arg;
if (!AggCheckCallContext(fcinfo, &aggcontext))
@@ -1970,6 +1984,9 @@ json_object_agg_transfn(PG_FUNCTION_ARGS)
if (PG_ARGISNULL(0))
{
+ Oid val_type;
+ JsonTypeCategory tcategory;
+ Oid outfuncoid;
/*
* Make the StringInfo in a context where it will persist for the
* duration of the aggregate call. Switching context is only needed
@@ -1977,15 +1994,38 @@ json_object_agg_transfn(PG_FUNCTION_ARGS)
* use the right context to enlarge the object if necessary.
*/
oldcontext = MemoryContextSwitchTo(aggcontext);
- state = makeStringInfo();
+ state = (JsonAggState *) palloc(sizeof(JsonAggState));
+ state->str = makeStringInfo();
MemoryContextSwitchTo(oldcontext);
- appendStringInfoString(state, "{ ");
+ val_type = get_fn_expr_argtype(fcinfo->flinfo, 1);
+
+ if (val_type == InvalidOid)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("could not determine data type for argument 1")));
+
+ json_categorize_type(val_type,&tcategory, &outfuncoid);
+ state->key_category = tcategory;
+ state->key_output_func = outfuncoid;
+
+ val_type = get_fn_expr_argtype(fcinfo->flinfo, 2);
+
+ if (val_type == InvalidOid)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("could not determine data type for argument 2")));
+
+ json_categorize_type(val_type,&tcategory, &outfuncoid);
+ state->val_category = tcategory;
+ state->val_output_func = outfuncoid;
+
+ appendStringInfoString(state->str, "{ ");
}
else
{
- state = (StringInfo) PG_GETARG_POINTER(0);
- appendStringInfoString(state, ", ");
+ state = (JsonAggState *) PG_GETARG_POINTER(0);
+ appendStringInfoString(state->str, ", ");
}
/*
@@ -1995,12 +2035,6 @@ json_object_agg_transfn(PG_FUNCTION_ARGS)
* type UNKNOWN, which fortunately does not matter to us, since
* unknownout() works fine.
*/
- val_type = get_fn_expr_argtype(fcinfo->flinfo, 1);
-
- if (val_type == InvalidOid)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
- errmsg("could not determine data type for argument %d", 1)));
if (PG_ARGISNULL(1))
ereport(ERROR,
@@ -2009,23 +2043,18 @@ json_object_agg_transfn(PG_FUNCTION_ARGS)
arg = PG_GETARG_DATUM(1);
- add_json(arg, false, state, val_type, true);
+ datum_to_json(arg, false, state->str, state->key_category,
+ state->key_output_func, true);
- appendStringInfoString(state, " : ");
-
- val_type = get_fn_expr_argtype(fcinfo->flinfo, 2);
-
- if (val_type == InvalidOid)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
- errmsg("could not determine data type for argument %d", 2)));
+ appendStringInfoString(state->str, " : ");
if (PG_ARGISNULL(2))
arg = (Datum) 0;
else
arg = PG_GETARG_DATUM(2);
- add_json(arg, PG_ARGISNULL(2), state, val_type, false);
+ datum_to_json(arg, PG_ARGISNULL(2), state->str, state->val_category,
+ state->val_output_func, false);
PG_RETURN_POINTER(state);
}
@@ -2036,19 +2065,19 @@ json_object_agg_transfn(PG_FUNCTION_ARGS)
Datum
json_object_agg_finalfn(PG_FUNCTION_ARGS)
{
- StringInfo state;
+ JsonAggState *state;
/* cannot be called directly because of internal-type argument */
Assert(AggCheckCallContext(fcinfo, NULL));
- state = PG_ARGISNULL(0) ? NULL : (StringInfo) PG_GETARG_POINTER(0);
+ state = PG_ARGISNULL(0) ? NULL : (JsonAggState *) PG_GETARG_POINTER(0);
/* NULL result for no rows in, as is standard with aggregates */
if (state == NULL)
PG_RETURN_NULL();
/* Else return state with appropriate object terminator added */
- PG_RETURN_TEXT_P(catenate_stringinfo_string(state, " }"));
+ PG_RETURN_TEXT_P(catenate_stringinfo_string(state->str, " }"));
}
/*
diff --git a/src/backend/utils/adt/jsonb.c b/src/backend/utils/adt/jsonb.c
index 154bc36..e0cf53c 100644
--- a/src/backend/utils/adt/jsonb.c
+++ b/src/backend/utils/adt/jsonb.c
@@ -59,6 +59,15 @@ typedef enum /* type categories for datum_to_jsonb */
JSONBTYPE_OTHER /* all else */
} JsonbTypeCategory;
+typedef struct JsonbAggState
+{
+ JsonbInState *res;
+ JsonbTypeCategory key_category;
+ Oid key_output_func;
+ JsonbTypeCategory val_category;
+ Oid val_output_func;
+} JsonbAggState;
+
static inline Datum jsonb_from_cstring(char *json, int len);
static size_t checkStringLen(size_t len);
static void jsonb_in_object_start(void *pstate);
@@ -1573,12 +1582,10 @@ clone_parse_state(JsonbParseState *state)
Datum
jsonb_agg_transfn(PG_FUNCTION_ARGS)
{
- Oid val_type = get_fn_expr_argtype(fcinfo->flinfo, 1);
MemoryContext oldcontext,
aggcontext;
+ JsonbAggState *state;
JsonbInState elem;
- JsonbTypeCategory tcategory;
- Oid outfuncoid;
Datum val;
JsonbInState *result;
bool single_scalar = false;
@@ -1587,48 +1594,60 @@ jsonb_agg_transfn(PG_FUNCTION_ARGS)
JsonbValue v;
JsonbIteratorToken type;
- if (val_type == InvalidOid)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
- errmsg("could not determine input data type")));
-
if (!AggCheckCallContext(fcinfo, &aggcontext))
{
/* cannot be called directly because of internal-type argument */
elog(ERROR, "jsonb_agg_transfn called in non-aggregate context");
}
- /* turn the argument into jsonb in the normal function context */
-
- val = PG_ARGISNULL(1) ? (Datum) 0 : PG_GETARG_DATUM(1);
-
- jsonb_categorize_type(val_type,
- &tcategory, &outfuncoid);
-
- memset(&elem, 0, sizeof(JsonbInState));
-
- datum_to_jsonb(val, PG_ARGISNULL(1), &elem, tcategory, outfuncoid, false);
-
- jbelem = JsonbValueToJsonb(elem.res);
-
- /* switch to the aggregate context for accumulation operations */
-
- oldcontext = MemoryContextSwitchTo(aggcontext);
-
/* set up the accumulator on the first go round */
if (PG_ARGISNULL(0))
{
+
+ Oid val_type = get_fn_expr_argtype(fcinfo->flinfo, 1);
+ JsonbTypeCategory tcategory;
+ Oid outfuncoid;
+
+ if (val_type == InvalidOid)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("could not determine input data type")));
+
+ oldcontext = MemoryContextSwitchTo(aggcontext);
+ state = palloc(sizeof(JsonbAggState));
result = palloc0(sizeof(JsonbInState));
+ state->res = result;
result->res = pushJsonbValue(&result->parseState,
WJB_BEGIN_ARRAY, NULL);
+ MemoryContextSwitchTo(oldcontext);
+ jsonb_categorize_type(val_type,
+ &tcategory, &outfuncoid);
+ state->val_category = tcategory;
+ state->val_output_func = outfuncoid;
}
else
{
- result = (JsonbInState *) PG_GETARG_POINTER(0);
+ state = (JsonbAggState *) PG_GETARG_POINTER(0);
+ result = state->res;
}
+ /* turn the argument into jsonb in the normal function context */
+
+ val = PG_ARGISNULL(1) ? (Datum) 0 : PG_GETARG_DATUM(1);
+
+ memset(&elem, 0, sizeof(JsonbInState));
+
+ datum_to_jsonb(val, PG_ARGISNULL(1), &elem, state->val_category,
+ state->val_output_func, false);
+
+ jbelem = JsonbValueToJsonb(elem.res);
+
+ /* switch to the aggregate context for accumulation operations */
+
+ oldcontext = MemoryContextSwitchTo(aggcontext);
+
it = JsonbIteratorInit(&jbelem->root);
while ((type = JsonbIteratorNext(&it, &v, false)) != WJB_DONE)
@@ -1669,7 +1688,6 @@ jsonb_agg_transfn(PG_FUNCTION_ARGS)
v.val.numeric =
DatumGetNumeric(DirectFunctionCall1(numeric_uplus,
NumericGetDatum(v.val.numeric)));
-
}
result->res = pushJsonbValue(&result->parseState,
type, &v);
@@ -1681,13 +1699,13 @@ jsonb_agg_transfn(PG_FUNCTION_ARGS)
MemoryContextSwitchTo(oldcontext);
- PG_RETURN_POINTER(result);
+ PG_RETURN_POINTER(state);
}
Datum
jsonb_agg_finalfn(PG_FUNCTION_ARGS)
{
- JsonbInState *arg;
+ JsonbAggState *arg;
JsonbInState result;
Jsonb *out;
@@ -1697,7 +1715,7 @@ jsonb_agg_finalfn(PG_FUNCTION_ARGS)
if (PG_ARGISNULL(0))
PG_RETURN_NULL(); /* returns null iff no input values */
- arg = (JsonbInState *) PG_GETARG_POINTER(0);
+ arg = (JsonbAggState *) PG_GETARG_POINTER(0);
/*
* We need to do a shallow clone of the argument in case the final
@@ -1706,12 +1724,11 @@ jsonb_agg_finalfn(PG_FUNCTION_ARGS)
* values, just add the final array end marker.
*/
- result.parseState = clone_parse_state(arg->parseState);
+ result.parseState = clone_parse_state(arg->res->parseState);
result.res = pushJsonbValue(&result.parseState,
WJB_END_ARRAY, NULL);
-
out = JsonbValueToJsonb(result.res);
PG_RETURN_POINTER(out);
@@ -1723,12 +1740,10 @@ jsonb_agg_finalfn(PG_FUNCTION_ARGS)
Datum
jsonb_object_agg_transfn(PG_FUNCTION_ARGS)
{
- Oid val_type;
MemoryContext oldcontext,
aggcontext;
JsonbInState elem;
- JsonbTypeCategory tcategory;
- Oid outfuncoid;
+ JsonbAggState *state;
Datum val;
JsonbInState *result;
bool single_scalar;
@@ -1744,14 +1759,53 @@ jsonb_object_agg_transfn(PG_FUNCTION_ARGS)
elog(ERROR, "jsonb_object_agg_transfn called in non-aggregate context");
}
- /* turn the argument into jsonb in the normal function context */
+ /* set up the accumulator on the first go round */
- val_type = get_fn_expr_argtype(fcinfo->flinfo, 1);
+ if (PG_ARGISNULL(0))
+ {
+ JsonbTypeCategory tcategory;
+ Oid outfuncoid;
+ Oid val_type;
- if (val_type == InvalidOid)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
- errmsg("could not determine input data type")));
+ oldcontext = MemoryContextSwitchTo(aggcontext);
+ state = palloc(sizeof(JsonbAggState));
+ result = palloc0(sizeof(JsonbInState));
+ state->res = result;
+ result->res = pushJsonbValue(&result->parseState,
+ WJB_BEGIN_OBJECT, NULL);
+ MemoryContextSwitchTo(aggcontext);
+
+ val_type = get_fn_expr_argtype(fcinfo->flinfo, 1);
+
+ if (val_type == InvalidOid)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("could not determine input data type")));
+
+ jsonb_categorize_type(val_type,
+ &tcategory, &outfuncoid);
+ state->key_category = tcategory;
+ state->key_output_func = outfuncoid;
+
+ val_type = get_fn_expr_argtype(fcinfo->flinfo, 2);
+
+ if (val_type == InvalidOid)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("could not determine input data type")));
+
+ jsonb_categorize_type(val_type,
+ &tcategory, &outfuncoid);
+ state->val_category = tcategory;
+ state->val_output_func = outfuncoid;
+ }
+ else
+ {
+ state = (JsonbAggState *) PG_GETARG_POINTER(0);
+ result = state->res;
+ }
+
+ /* turn the argument into jsonb in the normal function context */
if (PG_ARGISNULL(1))
ereport(ERROR,
@@ -1760,53 +1814,28 @@ jsonb_object_agg_transfn(PG_FUNCTION_ARGS)
val = PG_GETARG_DATUM(1);
- jsonb_categorize_type(val_type,
- &tcategory, &outfuncoid);
-
memset(&elem, 0, sizeof(JsonbInState));
- datum_to_jsonb(val, false, &elem, tcategory, outfuncoid, true);
+ datum_to_jsonb(val, false, &elem, state->key_category,
+ state->key_output_func, true);
jbkey = JsonbValueToJsonb(elem.res);
- val_type = get_fn_expr_argtype(fcinfo->flinfo, 2);
-
- if (val_type == InvalidOid)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
- errmsg("could not determine input data type")));
-
val = PG_ARGISNULL(2) ? (Datum) 0 : PG_GETARG_DATUM(2);
- jsonb_categorize_type(val_type,
- &tcategory, &outfuncoid);
-
memset(&elem, 0, sizeof(JsonbInState));
- datum_to_jsonb(val, PG_ARGISNULL(2), &elem, tcategory, outfuncoid, false);
+ datum_to_jsonb(val, PG_ARGISNULL(2), &elem, state->val_category,
+ state->val_output_func, false);
jbval = JsonbValueToJsonb(elem.res);
+ it = JsonbIteratorInit(&jbkey->root);
+
/* switch to the aggregate context for accumulation operations */
oldcontext = MemoryContextSwitchTo(aggcontext);
- /* set up the accumulator on the first go round */
-
- if (PG_ARGISNULL(0))
- {
- result = palloc0(sizeof(JsonbInState));
- result->res = pushJsonbValue(&result->parseState,
- WJB_BEGIN_OBJECT, NULL);
-
- }
- else
- {
- result = (JsonbInState *) PG_GETARG_POINTER(0);
- }
-
- it = JsonbIteratorInit(&jbkey->root);
-
/*
* keys should be scalar, and we should have already checked for that
* above when calling datum_to_jsonb, so we only need to look for these
@@ -1895,7 +1924,6 @@ jsonb_object_agg_transfn(PG_FUNCTION_ARGS)
v.val.numeric =
DatumGetNumeric(DirectFunctionCall1(numeric_uplus,
NumericGetDatum(v.val.numeric)));
-
}
result->res = pushJsonbValue(&result->parseState,
single_scalar ? WJB_VALUE : type,
@@ -1908,13 +1936,13 @@ jsonb_object_agg_transfn(PG_FUNCTION_ARGS)
MemoryContextSwitchTo(oldcontext);
- PG_RETURN_POINTER(result);
+ PG_RETURN_POINTER(state);
}
Datum
jsonb_object_agg_finalfn(PG_FUNCTION_ARGS)
{
- JsonbInState *arg;
+ JsonbAggState *arg;
JsonbInState result;
Jsonb *out;
@@ -1924,21 +1952,20 @@ jsonb_object_agg_finalfn(PG_FUNCTION_ARGS)
if (PG_ARGISNULL(0))
PG_RETURN_NULL(); /* returns null iff no input values */
- arg = (JsonbInState *) PG_GETARG_POINTER(0);
+ arg = (JsonbAggState *) PG_GETARG_POINTER(0);
/*
- * We need to do a shallow clone of the argument in case the final
- * function is called more than once, so we avoid changing the argument. A
- * shallow clone is sufficient as we aren't going to change any of the
- * values, just add the final object end marker.
+ * We need to do a shallow clone of the argument's res field in case the
+ * final function is called more than once, so we avoid changing the
+ * it. A shallow clone is sufficient as we aren't going to change any of
+ * the values, just add the final object end marker.
*/
- result.parseState = clone_parse_state(arg->parseState);
+ result.parseState = clone_parse_state(arg->res->parseState);
result.res = pushJsonbValue(&result.parseState,
WJB_END_OBJECT, NULL);
-
out = JsonbValueToJsonb(result.res);
PG_RETURN_POINTER(out);
--
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