diff options
Diffstat (limited to 'src/backend/parser/parse_expr.c')
| -rw-r--r-- | src/backend/parser/parse_expr.c | 490 |
1 files changed, 480 insertions, 10 deletions
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c index 0b972ea6322..ee316a91979 100644 --- a/src/backend/parser/parse_expr.c +++ b/src/backend/parser/parse_expr.c @@ -86,6 +86,8 @@ static Node *transformJsonArrayQueryConstructor(ParseState *pstate, static Node *transformJsonObjectAgg(ParseState *pstate, JsonObjectAgg *agg); static Node *transformJsonArrayAgg(ParseState *pstate, JsonArrayAgg *agg); static Node *transformJsonIsPredicate(ParseState *pstate, JsonIsPredicate *p); +static Node *transformJsonFuncExpr(ParseState *pstate, JsonFuncExpr *p); +static Node *transformJsonValueExpr(ParseState *pstate, JsonValueExpr *jve); static Node *make_row_comparison_op(ParseState *pstate, List *opname, List *largs, List *rargs, int location); static Node *make_row_distinct_op(ParseState *pstate, List *opname, @@ -337,6 +339,14 @@ transformExprRecurse(ParseState *pstate, Node *expr) result = transformJsonIsPredicate(pstate, (JsonIsPredicate *) expr); break; + case T_JsonFuncExpr: + result = transformJsonFuncExpr(pstate, (JsonFuncExpr *) expr); + break; + + case T_JsonValueExpr: + result = transformJsonValueExpr(pstate, (JsonValueExpr *) expr); + break; + default: /* should not reach here */ elog(ERROR, "unrecognized node type: %d", (int) nodeTag(expr)); @@ -3218,8 +3228,8 @@ makeCaseTestExpr(Node *expr) * default format otherwise. */ static Node * -transformJsonValueExpr(ParseState *pstate, JsonValueExpr *ve, - JsonFormatType default_format) +transformJsonValueExprExt(ParseState *pstate, JsonValueExpr *ve, + JsonFormatType default_format, bool isarg) { Node *expr = transformExprRecurse(pstate, (Node *) ve->raw_expr); Node *rawexpr; @@ -3238,6 +3248,8 @@ transformJsonValueExpr(ParseState *pstate, JsonValueExpr *ve, get_type_category_preferred(exprtype, &typcategory, &typispreferred); + rawexpr = expr; + if (ve->format->format_type != JS_FORMAT_DEFAULT) { if (ve->format->encoding != JS_ENC_DEFAULT && exprtype != BYTEAOID) @@ -3256,12 +3268,44 @@ transformJsonValueExpr(ParseState *pstate, JsonValueExpr *ve, else format = ve->format->format_type; } + else if (isarg) + { + /* Pass SQL/JSON item types directly without conversion to json[b]. */ + switch (exprtype) + { + case TEXTOID: + case NUMERICOID: + case BOOLOID: + case INT2OID: + case INT4OID: + case INT8OID: + case FLOAT4OID: + case FLOAT8OID: + case DATEOID: + case TIMEOID: + case TIMETZOID: + case TIMESTAMPOID: + case TIMESTAMPTZOID: + return expr; + + default: + if (typcategory == TYPCATEGORY_STRING) + return coerce_to_specific_type(pstate, expr, TEXTOID, + "JSON_VALUE_EXPR"); + /* else convert argument to json[b] type */ + break; + } + + format = default_format; + } else if (exprtype == JSONOID || exprtype == JSONBOID) format = JS_FORMAT_DEFAULT; /* do not format json[b] types */ else format = default_format; - if (format != JS_FORMAT_DEFAULT) + if (format == JS_FORMAT_DEFAULT) + expr = rawexpr; + else { Oid targettype = format == JS_FORMAT_JSONB ? JSONBOID : JSONOID; Node *orig = makeCaseTestExpr(expr); @@ -3269,7 +3313,7 @@ transformJsonValueExpr(ParseState *pstate, JsonValueExpr *ve, expr = orig; - if (exprtype != BYTEAOID && typcategory != TYPCATEGORY_STRING) + if (!isarg && exprtype != BYTEAOID && typcategory != TYPCATEGORY_STRING) ereport(ERROR, (errcode(ERRCODE_DATATYPE_MISMATCH), errmsg(ve->format->format_type == JS_FORMAT_DEFAULT ? @@ -3321,6 +3365,24 @@ transformJsonValueExpr(ParseState *pstate, JsonValueExpr *ve, } /* + * Transform JSON value expression using FORMAT JSON by default. + */ +static Node * +transformJsonValueExpr(ParseState *pstate, JsonValueExpr *jve) +{ + return transformJsonValueExprExt(pstate, jve, JS_FORMAT_JSON, false); +} + +/* + * Transform JSON value expression using unspecified format by default. + */ +static Node * +transformJsonValueExprDefault(ParseState *pstate, JsonValueExpr *jve) +{ + return transformJsonValueExprExt(pstate, jve, JS_FORMAT_DEFAULT, false); +} + +/* * Checks specified output format for its applicability to the target type. */ static void @@ -3576,8 +3638,7 @@ transformJsonObjectConstructor(ParseState *pstate, JsonObjectConstructor *ctor) { JsonKeyValue *kv = castNode(JsonKeyValue, lfirst(lc)); Node *key = transformExprRecurse(pstate, (Node *) kv->key); - Node *val = transformJsonValueExpr(pstate, kv->value, - JS_FORMAT_DEFAULT); + Node *val = transformJsonValueExprDefault(pstate, kv->value); args = lappend(args, key); args = lappend(args, val); @@ -3755,7 +3816,7 @@ transformJsonObjectAgg(ParseState *pstate, JsonObjectAgg *agg) Oid aggtype; key = transformExprRecurse(pstate, (Node *) agg->arg->key); - val = transformJsonValueExpr(pstate, agg->arg->value, JS_FORMAT_DEFAULT); + val = transformJsonValueExprDefault(pstate, agg->arg->value); args = list_make2(key, val); returning = transformJsonConstructorOutput(pstate, agg->constructor->output, @@ -3813,7 +3874,7 @@ transformJsonArrayAgg(ParseState *pstate, JsonArrayAgg *agg) const char *aggfnname; Oid aggtype; - arg = transformJsonValueExpr(pstate, agg->arg, JS_FORMAT_DEFAULT); + arg = transformJsonValueExprDefault(pstate, agg->arg); returning = transformJsonConstructorOutput(pstate, agg->constructor->output, list_make1(arg)); @@ -3861,8 +3922,7 @@ transformJsonArrayConstructor(ParseState *pstate, JsonArrayConstructor *ctor) foreach(lc, ctor->exprs) { JsonValueExpr *jsval = castNode(JsonValueExpr, lfirst(lc)); - Node *val = transformJsonValueExpr(pstate, jsval, - JS_FORMAT_DEFAULT); + Node *val = transformJsonValueExprDefault(pstate, jsval); args = lappend(args, val); } @@ -3945,3 +4005,413 @@ transformJsonIsPredicate(ParseState *pstate, JsonIsPredicate *pred) return makeJsonIsPredicate(expr, NULL, pred->value_type, pred->unique_keys, pred->location); } + +/* + * Transform a JSON PASSING clause. + */ +static void +transformJsonPassingArgs(ParseState *pstate, JsonFormatType format, List *args, + List **passing_values, List **passing_names) +{ + ListCell *lc; + + *passing_values = NIL; + *passing_names = NIL; + + foreach(lc, args) + { + JsonArgument *arg = castNode(JsonArgument, lfirst(lc)); + Node *expr = transformJsonValueExprExt(pstate, arg->val, + format, true); + + assign_expr_collations(pstate, expr); + + *passing_values = lappend(*passing_values, expr); + *passing_names = lappend(*passing_names, makeString(arg->name)); + } +} + +/* + * Transform a JSON BEHAVIOR clause. + */ +static JsonBehavior * +transformJsonBehavior(ParseState *pstate, JsonBehavior *behavior, + JsonBehaviorType default_behavior) +{ + JsonBehaviorType behavior_type; + Node *default_expr; + + behavior_type = behavior ? behavior->btype : default_behavior; + default_expr = behavior_type != JSON_BEHAVIOR_DEFAULT ? NULL : + transformExprRecurse(pstate, behavior->default_expr); + + return makeJsonBehavior(behavior_type, default_expr); +} + +/* + * Common code for JSON_VALUE, JSON_QUERY, JSON_EXISTS transformation + * into a JsonExpr node. + */ +static JsonExpr * +transformJsonExprCommon(ParseState *pstate, JsonFuncExpr *func) +{ + JsonExpr *jsexpr = makeNode(JsonExpr); + Node *pathspec; + JsonFormatType format; + + if (func->common->pathname) + ereport(ERROR, + (errcode(ERRCODE_SYNTAX_ERROR), + errmsg("JSON_TABLE path name is not allowed here"), + parser_errposition(pstate, func->location))); + + jsexpr->location = func->location; + jsexpr->op = func->op; + jsexpr->formatted_expr = transformJsonValueExpr(pstate, func->common->expr); + + assign_expr_collations(pstate, jsexpr->formatted_expr); + + /* format is determined by context item type */ + format = exprType(jsexpr->formatted_expr) == JSONBOID ? JS_FORMAT_JSONB : JS_FORMAT_JSON; + + jsexpr->result_coercion = NULL; + jsexpr->omit_quotes = false; + + jsexpr->format = func->common->expr->format; + + pathspec = transformExprRecurse(pstate, func->common->pathspec); + + jsexpr->path_spec = + coerce_to_target_type(pstate, pathspec, exprType(pathspec), + JSONPATHOID, -1, + COERCION_EXPLICIT, COERCE_IMPLICIT_CAST, + exprLocation(pathspec)); + if (!jsexpr->path_spec) + ereport(ERROR, + (errcode(ERRCODE_DATATYPE_MISMATCH), + errmsg("JSON path expression must be type %s, not type %s", + "jsonpath", format_type_be(exprType(pathspec))), + parser_errposition(pstate, exprLocation(pathspec)))); + + /* transform and coerce to json[b] passing arguments */ + transformJsonPassingArgs(pstate, format, func->common->passing, + &jsexpr->passing_values, &jsexpr->passing_names); + + if (func->op != JSON_EXISTS_OP) + jsexpr->on_empty = transformJsonBehavior(pstate, func->on_empty, + JSON_BEHAVIOR_NULL); + + jsexpr->on_error = transformJsonBehavior(pstate, func->on_error, + func->op == JSON_EXISTS_OP ? + JSON_BEHAVIOR_FALSE : + JSON_BEHAVIOR_NULL); + + return jsexpr; +} + +/* + * Assign default JSON returning type from the specified format or from + * the context item type. + */ +static void +assignDefaultJsonReturningType(Node *context_item, JsonFormat *context_format, + JsonReturning *ret) +{ + bool is_jsonb; + + ret->format = copyObject(context_format); + + if (ret->format->format_type == JS_FORMAT_DEFAULT) + is_jsonb = exprType(context_item) == JSONBOID; + else + is_jsonb = ret->format->format_type == JS_FORMAT_JSONB; + + ret->typid = is_jsonb ? JSONBOID : JSONOID; + ret->typmod = -1; +} + +/* + * Try to coerce expression to the output type or + * use json_populate_type() for composite, array and domain types or + * use coercion via I/O. + */ +static JsonCoercion * +coerceJsonExpr(ParseState *pstate, Node *expr, const JsonReturning *returning) +{ + char typtype; + JsonCoercion *coercion = makeNode(JsonCoercion); + + coercion->expr = coerceJsonFuncExpr(pstate, expr, returning, false); + + if (coercion->expr) + { + if (coercion->expr == expr) + coercion->expr = NULL; + + return coercion; + } + + typtype = get_typtype(returning->typid); + + if (returning->typid == RECORDOID || + typtype == TYPTYPE_COMPOSITE || + typtype == TYPTYPE_DOMAIN || + type_is_array(returning->typid)) + coercion->via_populate = true; + else + coercion->via_io = true; + + return coercion; +} + +/* + * Transform a JSON output clause of JSON_VALUE and JSON_QUERY. + */ +static void +transformJsonFuncExprOutput(ParseState *pstate, JsonFuncExpr *func, + JsonExpr *jsexpr) +{ + Node *expr = jsexpr->formatted_expr; + + jsexpr->returning = transformJsonOutput(pstate, func->output, false); + + /* JSON_VALUE returns text by default */ + if (func->op == JSON_VALUE_OP && !OidIsValid(jsexpr->returning->typid)) + { + jsexpr->returning->typid = TEXTOID; + jsexpr->returning->typmod = -1; + } + + if (OidIsValid(jsexpr->returning->typid)) + { + JsonReturning ret; + + if (func->op == JSON_VALUE_OP && + jsexpr->returning->typid != JSONOID && + jsexpr->returning->typid != JSONBOID) + { + /* Forced coercion via I/O for JSON_VALUE for non-JSON types */ + jsexpr->result_coercion = makeNode(JsonCoercion); + jsexpr->result_coercion->expr = NULL; + jsexpr->result_coercion->via_io = true; + return; + } + + assignDefaultJsonReturningType(jsexpr->formatted_expr, jsexpr->format, &ret); + + if (ret.typid != jsexpr->returning->typid || + ret.typmod != jsexpr->returning->typmod) + { + Node *placeholder = makeCaseTestExpr(expr); + + Assert(((CaseTestExpr *) placeholder)->typeId == ret.typid); + Assert(((CaseTestExpr *) placeholder)->typeMod == ret.typmod); + + jsexpr->result_coercion = coerceJsonExpr(pstate, placeholder, + jsexpr->returning); + } + } + else + assignDefaultJsonReturningType(jsexpr->formatted_expr, jsexpr->format, + jsexpr->returning); +} + +/* + * Coerce a expression in JSON DEFAULT behavior to the target output type. + */ +static Node * +coerceDefaultJsonExpr(ParseState *pstate, JsonExpr *jsexpr, Node *defexpr) +{ + int location; + Oid exprtype; + + if (!defexpr) + return NULL; + + exprtype = exprType(defexpr); + location = exprLocation(defexpr); + + if (location < 0) + location = jsexpr->location; + + defexpr = coerce_to_target_type(pstate, + defexpr, + exprtype, + jsexpr->returning->typid, + jsexpr->returning->typmod, + COERCION_EXPLICIT, + COERCE_IMPLICIT_CAST, + location); + + if (!defexpr) + ereport(ERROR, + (errcode(ERRCODE_CANNOT_COERCE), + errmsg("cannot cast DEFAULT expression type %s to %s", + format_type_be(exprtype), + format_type_be(jsexpr->returning->typid)), + parser_errposition(pstate, location))); + + return defexpr; +} + +/* + * Initialize SQL/JSON item coercion from the SQL type "typid" to the target + * "returning" type. + */ +static JsonCoercion * +initJsonItemCoercion(ParseState *pstate, Oid typid, + const JsonReturning *returning) +{ + Node *expr; + + if (typid == UNKNOWNOID) + { + expr = (Node *) makeNullConst(UNKNOWNOID, -1, InvalidOid); + } + else + { + CaseTestExpr *placeholder = makeNode(CaseTestExpr); + + placeholder->typeId = typid; + placeholder->typeMod = -1; + placeholder->collation = InvalidOid; + + expr = (Node *) placeholder; + } + + return coerceJsonExpr(pstate, expr, returning); +} + +static void +initJsonItemCoercions(ParseState *pstate, JsonItemCoercions *coercions, + const JsonReturning *returning, Oid contextItemTypeId) +{ + struct + { + JsonCoercion **coercion; + Oid typid; + } *p, + coercionTypids[] = + { + { &coercions->null, UNKNOWNOID }, + { &coercions->string, TEXTOID }, + { &coercions->numeric, NUMERICOID }, + { &coercions->boolean, BOOLOID }, + { &coercions->date, DATEOID }, + { &coercions->time, TIMEOID }, + { &coercions->timetz, TIMETZOID }, + { &coercions->timestamp, TIMESTAMPOID }, + { &coercions->timestamptz, TIMESTAMPTZOID }, + { &coercions->composite, contextItemTypeId }, + { NULL, InvalidOid } + }; + + for (p = coercionTypids; p->coercion; p++) + *p->coercion = initJsonItemCoercion(pstate, p->typid, returning); +} + +/* + * Transform JSON_VALUE, JSON_QUERY, JSON_EXISTS functions into a JsonExpr node. + */ +static Node * +transformJsonFuncExpr(ParseState *pstate, JsonFuncExpr *func) +{ + JsonExpr *jsexpr = transformJsonExprCommon(pstate, func); + const char *func_name = NULL; + Node *contextItemExpr = jsexpr->formatted_expr; + + switch (func->op) + { + case JSON_VALUE_OP: + func_name = "JSON_VALUE"; + + transformJsonFuncExprOutput(pstate, func, jsexpr); + + jsexpr->returning->format->format_type = JS_FORMAT_DEFAULT; + jsexpr->returning->format->encoding = JS_ENC_DEFAULT; + + jsexpr->on_empty->default_expr = + coerceDefaultJsonExpr(pstate, jsexpr, + jsexpr->on_empty->default_expr); + + jsexpr->on_error->default_expr = + coerceDefaultJsonExpr(pstate, jsexpr, + jsexpr->on_error->default_expr); + + jsexpr->coercions = makeNode(JsonItemCoercions); + initJsonItemCoercions(pstate, jsexpr->coercions, jsexpr->returning, + exprType(contextItemExpr)); + + break; + + case JSON_QUERY_OP: + func_name = "JSON_QUERY"; + + transformJsonFuncExprOutput(pstate, func, jsexpr); + + jsexpr->on_empty->default_expr = + coerceDefaultJsonExpr(pstate, jsexpr, + jsexpr->on_empty->default_expr); + + jsexpr->on_error->default_expr = + coerceDefaultJsonExpr(pstate, jsexpr, + jsexpr->on_error->default_expr); + + jsexpr->wrapper = func->wrapper; + jsexpr->omit_quotes = func->omit_quotes; + + break; + + case JSON_EXISTS_OP: + func_name = "JSON_EXISTS"; + + jsexpr->returning = transformJsonOutput(pstate, func->output, false); + + jsexpr->returning->format->format_type = JS_FORMAT_DEFAULT; + jsexpr->returning->format->encoding = JS_ENC_DEFAULT; + + if (!OidIsValid(jsexpr->returning->typid)) + { + jsexpr->returning->typid = BOOLOID; + jsexpr->returning->typmod = -1; + } + else if (jsexpr->returning->typid != BOOLOID) + { + CaseTestExpr *placeholder = makeNode(CaseTestExpr); + int location = exprLocation((Node *) jsexpr); + + placeholder->typeId = BOOLOID; + placeholder->typeMod = -1; + placeholder->collation = InvalidOid; + + jsexpr->result_coercion = makeNode(JsonCoercion); + jsexpr->result_coercion->expr = + coerce_to_target_type(pstate, (Node *) placeholder, BOOLOID, + jsexpr->returning->typid, + jsexpr->returning->typmod, + COERCION_EXPLICIT, + COERCE_IMPLICIT_CAST, + location); + + if (!jsexpr->result_coercion->expr) + ereport(ERROR, + (errcode(ERRCODE_CANNOT_COERCE), + errmsg("cannot cast type %s to %s", + format_type_be(BOOLOID), + format_type_be(jsexpr->returning->typid)), + parser_coercion_errposition(pstate, location, (Node *) jsexpr))); + + if (jsexpr->result_coercion->expr == (Node *) placeholder) + jsexpr->result_coercion->expr = NULL; + } + break; + } + + if (exprType(contextItemExpr) != JSONBOID) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("%s() is not yet implemented for json type", func_name), + parser_errposition(pstate, func->location))); + + return (Node *) jsexpr; +} |