parse_jsontable.c File Reference

#include "postgres.h"
#include "catalog/pg_type.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "optimizer/optimizer.h"
#include "parser/parse_clause.h"
#include "parser/parse_collate.h"
#include "parser/parse_expr.h"
#include "parser/parse_relation.h"
#include "parser/parse_type.h"
#include "utils/fmgrprotos.h"
#include "utils/json.h"
#include "utils/lsyscache.h"

Include dependency graph for parse_jsontable.c:

Go to the source code of this file.

Data Structures
struct	JsonTableParseContext

Typedefs
typedef struct JsonTableParseContext	JsonTableParseContext

Functions
static JsonTablePlan *	transformJsonTableColumns (JsonTableParseContext *cxt, List *columns, List *passingArgs, JsonTablePathSpec *pathspec)
static JsonTablePlan *	transformJsonTableNestedColumns (JsonTableParseContext *cxt, List *passingArgs, List *columns)
static JsonFuncExpr *	transformJsonTableColumn (JsonTableColumn *jtc, Node *contextItemExpr, List *passingArgs)
static bool	isCompositeType (Oid typid)
static JsonTablePlan *	makeJsonTablePathScan (JsonTablePathSpec *pathspec, bool errorOnError, int colMin, int colMax, JsonTablePlan *childplan)
static void	CheckDuplicateColumnOrPathNames (JsonTableParseContext *cxt, List *columns)
static bool	LookupPathOrColumnName (JsonTableParseContext *cxt, char *name)
static char *	generateJsonTablePathName (JsonTableParseContext *cxt)
static JsonTablePlan *	makeJsonTableSiblingJoin (JsonTablePlan *lplan, JsonTablePlan *rplan)
ParseNamespaceItem *	transformJsonTable (ParseState *pstate, JsonTable *jt)

Typedef Documentation

JsonTableParseContext

typedef struct JsonTableParseContext JsonTableParseContext

Function Documentation

CheckDuplicateColumnOrPathNames()

static void CheckDuplicateColumnOrPathNames ( JsonTableParseContext *  cxt, List *  columns  )

static

Definition at line 171 of file parse_jsontable.c.

{
    ListCell   *lc1;
 
    foreach(lc1, columns)
    {
        JsonTableColumn *jtc = castNode(JsonTableColumn, lfirst(lc1));
 
        if (jtc->coltype == JTC_NESTED)
        {
            if (jtc->pathspec->name)
            {
                if (LookupPathOrColumnName(cxt, jtc->pathspec->name))
                    ereport(ERROR,
                            errcode(ERRCODE_DUPLICATE_ALIAS),
                            errmsg("duplicate JSON_TABLE column or path name: %s",
                                   jtc->pathspec->name),
                            parser_errposition(cxt->pstate,
                                               jtc->pathspec->name_location));
                cxt->pathNames = lappend(cxt->pathNames, jtc->pathspec->name);
            }
 
            CheckDuplicateColumnOrPathNames(cxt, jtc->columns);
        }
        else
        {
            if (LookupPathOrColumnName(cxt, jtc->name))
                ereport(ERROR,
                        errcode(ERRCODE_DUPLICATE_ALIAS),
                        errmsg("duplicate JSON_TABLE column or path name: %s",
                               jtc->name),
                        parser_errposition(cxt->pstate, jtc->location));
            cxt->pathNames = lappend(cxt->pathNames, jtc->name);
        }
    }
}

References castNode, CheckDuplicateColumnOrPathNames(), JsonTableColumn::coltype, JsonTableColumn::columns, ereport, errcode(), errmsg(), ERROR, JTC_NESTED, lappend(), lfirst, JsonTableColumn::location, LookupPathOrColumnName(), JsonTablePathSpec::name, JsonTableColumn::name, JsonTablePathSpec::name_location, parser_errposition(), JsonTableParseContext::pathNames, JsonTableColumn::pathspec, and JsonTableParseContext::pstate.

Referenced by CheckDuplicateColumnOrPathNames(), and transformJsonTable().

generateJsonTablePathName()

static char * generateJsonTablePathName ( JsonTableParseContext *  cxt )

static

Definition at line 229 of file parse_jsontable.c.

{
    char        namebuf[32];
    char       *name = namebuf;
 
    snprintf(namebuf, sizeof(namebuf), "json_table_path_%d",
             cxt->pathNameId++);
 
    name = pstrdup(name);
    cxt->pathNames = lappend(cxt->pathNames, name);
 
    return name;
}

References lappend(), name, JsonTableParseContext::pathNameId, JsonTableParseContext::pathNames, pstrdup(), and snprintf.

Referenced by transformJsonTable(), and transformJsonTableNestedColumns().

isCompositeType()

static bool isCompositeType ( Oid  typid )

static

Definition at line 375 of file parse_jsontable.c.

{
    char        typtype = get_typtype(typid);
 
    return typid == JSONOID ||
        typid == JSONBOID ||
        typid == RECORDOID ||
        type_is_array(typid) ||
        typtype == TYPTYPE_COMPOSITE ||
    /* domain over one of the above? */
        (typtype == TYPTYPE_DOMAIN &&
         isCompositeType(getBaseType(typid)));
}

References get_typtype(), getBaseType(), isCompositeType(), and type_is_array.

Referenced by AlterTypeNamespaceInternal(), isCompositeType(), and transformJsonTableColumns().

LookupPathOrColumnName()

static bool LookupPathOrColumnName ( JsonTableParseContext *  cxt, char *  name  )

static

Definition at line 214 of file parse_jsontable.c.

{
    ListCell   *lc;
 
    foreach(lc, cxt->pathNames)
    {
        if (strcmp(name, (const char *) lfirst(lc)) == 0)
            return true;
    }
 
    return false;
}

References lfirst, name, and JsonTableParseContext::pathNames.

Referenced by CheckDuplicateColumnOrPathNames().

makeJsonTablePathScan()

static JsonTablePlan * makeJsonTablePathScan ( JsonTablePathSpec *  pathspec, bool  errorOnError, int  colMin, int  colMax, JsonTablePlan *  childplan  )

static

Definition at line 497 of file parse_jsontable.c.

{
    JsonTablePathScan *scan = makeNode(JsonTablePathScan);
    char       *pathstring;
    Const      *value;
 
    Assert(IsA(pathspec->string, A_Const));
    pathstring = castNode(A_Const, pathspec->string)->val.sval.sval;
    value = makeConst(JSONPATHOID, -1, InvalidOid, -1,
                      DirectFunctionCall1(jsonpath_in,
                                          CStringGetDatum(pathstring)),
                      false, false);
 
    scan->plan.type = T_JsonTablePathScan;
    scan->path = makeJsonTablePath(value, pathspec->name);
    scan->errorOnError = errorOnError;
 
    scan->child = childplan;
 
    scan->colMin = colMin;
    scan->colMax = colMax;
 
    return (JsonTablePlan *) scan;
}

References Assert, castNode, JsonTablePathScan::child, JsonTablePathScan::colMax, JsonTablePathScan::colMin, CStringGetDatum(), DirectFunctionCall1, JsonTablePathScan::errorOnError, InvalidOid, IsA, jsonpath_in(), makeConst(), makeJsonTablePath(), makeNode, JsonTablePathSpec::name, JsonTablePathScan::path, JsonTablePathScan::plan, JsonTablePathSpec::string, and value.

Referenced by transformJsonTableColumns().

makeJsonTableSiblingJoin()

static JsonTablePlan * makeJsonTableSiblingJoin ( JsonTablePlan *  lplan, JsonTablePlan *  rplan  )

static

Definition at line 532 of file parse_jsontable.c.

{
    JsonTableSiblingJoin *join = makeNode(JsonTableSiblingJoin);
 
    join->plan.type = T_JsonTableSiblingJoin;
    join->lplan = lplan;
    join->rplan = rplan;
 
    return (JsonTablePlan *) join;
}

References JsonTableSiblingJoin::lplan, makeNode, JsonTableSiblingJoin::plan, and JsonTableSiblingJoin::rplan.

Referenced by transformJsonTableNestedColumns().

transformJsonTable()

ParseNamespaceItem * transformJsonTable	(	ParseState *	pstate,
		JsonTable *	jt
	)

Definition at line 74 of file parse_jsontable.c.

{
    TableFunc  *tf;
    JsonFuncExpr *jfe;
    JsonExpr   *je;
    JsonTablePathSpec *rootPathSpec = jt->pathspec;
    bool        is_lateral;
    JsonTableParseContext cxt = {pstate};
 
    Assert(IsA(rootPathSpec->string, A_Const) &&
           castNode(A_Const, rootPathSpec->string)->val.node.type == T_String);
 
    if (jt->on_error &&
        jt->on_error->btype != JSON_BEHAVIOR_ERROR &&
        jt->on_error->btype != JSON_BEHAVIOR_EMPTY &&
        jt->on_error->btype != JSON_BEHAVIOR_EMPTY_ARRAY)
        ereport(ERROR,
                errcode(ERRCODE_SYNTAX_ERROR),
                errmsg("invalid %s behavior", "ON ERROR"),
                errdetail("Only EMPTY [ ARRAY ] or ERROR is allowed in the top-level ON ERROR clause."),
                parser_errposition(pstate, jt->on_error->location));
 
    cxt.pathNameId = 0;
    if (rootPathSpec->name == NULL)
        rootPathSpec->name = generateJsonTablePathName(&cxt);
    cxt.pathNames = list_make1(rootPathSpec->name);
    CheckDuplicateColumnOrPathNames(&cxt, jt->columns);
 
    /*
     * We make lateral_only names of this level visible, whether or not the
     * RangeTableFunc is explicitly marked LATERAL.  This is needed for SQL
     * spec compliance and seems useful on convenience grounds for all
     * functions in FROM.
     *
     * (LATERAL can't nest within a single pstate level, so we don't need
     * save/restore logic here.)
     */
    Assert(!pstate->p_lateral_active);
    pstate->p_lateral_active = true;
 
    tf = makeNode(TableFunc);
    tf->functype = TFT_JSON_TABLE;
 
    /*
     * Transform JsonFuncExpr representing the top JSON_TABLE context_item and
     * pathspec into a dummy JSON_TABLE_OP JsonExpr.
     */
    jfe = makeNode(JsonFuncExpr);
    jfe->op = JSON_TABLE_OP;
    jfe->context_item = jt->context_item;
    jfe->pathspec = (Node *) rootPathSpec->string;
    jfe->passing = jt->passing;
    jfe->on_empty = NULL;
    jfe->on_error = jt->on_error;
    jfe->location = jt->location;
    tf->docexpr = transformExpr(pstate, (Node *) jfe, EXPR_KIND_FROM_FUNCTION);
 
    /*
     * Create a JsonTablePlan that will generate row pattern that becomes
     * source data for JSON path expressions in jt->columns.  This also adds
     * the columns' transformed JsonExpr nodes into tf->colvalexprs.
     */
    cxt.jt = jt;
    cxt.tf = tf;
    tf->plan = (Node *) transformJsonTableColumns(&cxt, jt->columns,
                                                  jt->passing,
                                                  rootPathSpec);
 
    /*
     * Copy the transformed PASSING arguments into the TableFunc node, because
     * they are evaluated separately from the JsonExpr that we just put in
     * TableFunc.docexpr.  JsonExpr.passing_values is still kept around for
     * get_json_table().
     */
    je = (JsonExpr *) tf->docexpr;
    tf->passingvalexprs = copyObject(je->passing_values);
 
    tf->ordinalitycol = -1;     /* undefine ordinality column number */
    tf->location = jt->location;
 
    pstate->p_lateral_active = false;
 
    /*
     * Mark the RTE as LATERAL if the user said LATERAL explicitly, or if
     * there are any lateral cross-references in it.
     */
    is_lateral = jt->lateral || contain_vars_of_level((Node *) tf, 0);
 
    return addRangeTableEntryForTableFunc(pstate,
                                          tf, jt->alias, is_lateral, true);
}

References addRangeTableEntryForTableFunc(), JsonTable::alias, Assert, JsonBehavior::btype, castNode, CheckDuplicateColumnOrPathNames(), JsonTable::columns, contain_vars_of_level(), JsonFuncExpr::context_item, JsonTable::context_item, copyObject, TableFunc::docexpr, ereport, errcode(), errdetail(), errmsg(), ERROR, EXPR_KIND_FROM_FUNCTION, TableFunc::functype, generateJsonTablePathName(), IsA, JSON_BEHAVIOR_EMPTY, JSON_BEHAVIOR_EMPTY_ARRAY, JSON_BEHAVIOR_ERROR, JSON_TABLE_OP, JsonTableParseContext::jt, JsonTable::lateral, list_make1, JsonFuncExpr::location, JsonTable::location, TableFunc::location, JsonBehavior::location, makeNode, JsonTablePathSpec::name, JsonFuncExpr::on_empty, JsonFuncExpr::on_error, JsonTable::on_error, JsonFuncExpr::op, ParseState::p_lateral_active, parser_errposition(), JsonFuncExpr::passing, JsonTable::passing, JsonExpr::passing_values, JsonTableParseContext::pathNameId, JsonTableParseContext::pathNames, JsonFuncExpr::pathspec, JsonTable::pathspec, JsonTablePathSpec::string, JsonTableParseContext::tf, TFT_JSON_TABLE, transformExpr(), and transformJsonTableColumns().

Referenced by transformFromClauseItem().

transformJsonTableColumn()

static JsonFuncExpr * transformJsonTableColumn ( JsonTableColumn *  jtc, Node *  contextItemExpr, List *  passingArgs  )

static

Definition at line 397 of file parse_jsontable.c.

{
    Node       *pathspec;
    JsonFuncExpr *jfexpr = makeNode(JsonFuncExpr);
 
    if (jtc->coltype == JTC_REGULAR)
        jfexpr->op = JSON_VALUE_OP;
    else if (jtc->coltype == JTC_EXISTS)
        jfexpr->op = JSON_EXISTS_OP;
    else
        jfexpr->op = JSON_QUERY_OP;
 
    /* Pass the column name so any runtime JsonExpr errors can print it. */
    Assert(jtc->name != NULL);
    jfexpr->column_name = pstrdup(jtc->name);
 
    jfexpr->context_item = makeJsonValueExpr((Expr *) contextItemExpr, NULL,
                                             makeJsonFormat(JS_FORMAT_DEFAULT,
                                                            JS_ENC_DEFAULT,
                                                            -1));
    if (jtc->pathspec)
        pathspec = (Node *) jtc->pathspec->string;
    else
    {
        /* Construct default path as '$."column_name"' */
        StringInfoData path;
 
        initStringInfo(&path);
 
        appendStringInfoString(&path, "$.");
        escape_json(&path, jtc->name);
 
        pathspec = makeStringConst(path.data, -1);
    }
    jfexpr->pathspec = pathspec;
    jfexpr->passing = passingArgs;
    jfexpr->output = makeNode(JsonOutput);
    jfexpr->output->typeName = jtc->typeName;
    jfexpr->output->returning = makeNode(JsonReturning);
    jfexpr->output->returning->format = jtc->format;
    jfexpr->on_empty = jtc->on_empty;
    jfexpr->on_error = jtc->on_error;
    jfexpr->quotes = jtc->quotes;
    jfexpr->wrapper = jtc->wrapper;
    jfexpr->location = jtc->location;
 
    return jfexpr;
}

References appendStringInfoString(), Assert, JsonTableColumn::coltype, JsonFuncExpr::column_name, JsonFuncExpr::context_item, escape_json(), initStringInfo(), JS_ENC_DEFAULT, JS_FORMAT_DEFAULT, JSON_EXISTS_OP, JSON_QUERY_OP, JSON_VALUE_OP, JTC_EXISTS, JTC_REGULAR, makeJsonFormat(), makeJsonValueExpr(), makeNode, makeStringConst(), JsonTableColumn::name, JsonFuncExpr::op, JsonTableColumn::pathspec, pstrdup(), and JsonTablePathSpec::string.

Referenced by transformJsonTableColumns().

transformJsonTableColumns()

static JsonTablePlan * transformJsonTableColumns ( JsonTableParseContext *  cxt, List *  columns, List *  passingArgs, JsonTablePathSpec *  pathspec  )

static

Definition at line 249 of file parse_jsontable.c.

{
    ParseState *pstate = cxt->pstate;
    JsonTable  *jt = cxt->jt;
    TableFunc  *tf = cxt->tf;
    ListCell   *col;
    bool        ordinality_found = false;
    bool        errorOnError = jt->on_error &&
        jt->on_error->btype == JSON_BEHAVIOR_ERROR;
    Oid         contextItemTypid = exprType(tf->docexpr);
    int         colMin,
                colMax;
    JsonTablePlan *childplan;
 
    /* Start of column range */
    colMin = list_length(tf->colvalexprs);
 
    foreach(col, columns)
    {
        JsonTableColumn *rawc = castNode(JsonTableColumn, lfirst(col));
        Oid         typid;
        int32       typmod;
        Oid         typcoll = InvalidOid;
        Node       *colexpr;
 
        if (rawc->coltype != JTC_NESTED)
        {
            Assert(rawc->name);
            tf->colnames = lappend(tf->colnames,
                                   makeString(pstrdup(rawc->name)));
        }
 
        /*
         * Determine the type and typmod for the new column. FOR ORDINALITY
         * columns are INTEGER by standard; the others are user-specified.
         */
        switch (rawc->coltype)
        {
            case JTC_FOR_ORDINALITY:
                if (ordinality_found)
                    ereport(ERROR,
                            (errcode(ERRCODE_SYNTAX_ERROR),
                             errmsg("only one FOR ORDINALITY column is allowed"),
                             parser_errposition(pstate, rawc->location)));
                ordinality_found = true;
                colexpr = NULL;
                typid = INT4OID;
                typmod = -1;
                break;
 
            case JTC_REGULAR:
                typenameTypeIdAndMod(pstate, rawc->typeName, &typid, &typmod);
 
                /*
                 * Use JTC_FORMATTED so as to use JSON_QUERY for this column
                 * if the specified type is one that's better handled using
                 * JSON_QUERY() or if non-default WRAPPER or QUOTES behavior
                 * is specified.
                 */
                if (isCompositeType(typid) ||
                    rawc->quotes != JS_QUOTES_UNSPEC ||
                    rawc->wrapper != JSW_UNSPEC)
                    rawc->coltype = JTC_FORMATTED;
 
                /* FALLTHROUGH */
            case JTC_FORMATTED:
            case JTC_EXISTS:
                {
                    JsonFuncExpr *jfe;
                    CaseTestExpr *param = makeNode(CaseTestExpr);
 
                    param->collation = InvalidOid;
                    param->typeId = contextItemTypid;
                    param->typeMod = -1;
 
                    jfe = transformJsonTableColumn(rawc, (Node *) param,
                                                   passingArgs);
 
                    colexpr = transformExpr(pstate, (Node *) jfe,
                                            EXPR_KIND_FROM_FUNCTION);
                    assign_expr_collations(pstate, colexpr);
 
                    typid = exprType(colexpr);
                    typmod = exprTypmod(colexpr);
                    typcoll = exprCollation(colexpr);
                    break;
                }
 
            case JTC_NESTED:
                continue;
 
            default:
                elog(ERROR, "unknown JSON_TABLE column type: %d", (int) rawc->coltype);
                break;
        }
 
        tf->coltypes = lappend_oid(tf->coltypes, typid);
        tf->coltypmods = lappend_int(tf->coltypmods, typmod);
        tf->colcollations = lappend_oid(tf->colcollations, typcoll);
        tf->colvalexprs = lappend(tf->colvalexprs, colexpr);
    }
 
    /* End of column range. */
    if (list_length(tf->colvalexprs) == colMin)
    {
        /* No columns in this Scan beside the nested ones. */
        colMax = colMin = -1;
    }
    else
        colMax = list_length(tf->colvalexprs) - 1;
 
    /* Recursively transform nested columns */
    childplan = transformJsonTableNestedColumns(cxt, passingArgs, columns);
 
    /* Create a "parent" scan responsible for all columns handled above. */
    return makeJsonTablePathScan(pathspec, errorOnError, colMin, colMax,
                                 childplan);
}

References Assert, assign_expr_collations(), JsonBehavior::btype, castNode, JsonTableColumn::coltype, TableFunc::docexpr, elog, ereport, errcode(), errmsg(), ERROR, EXPR_KIND_FROM_FUNCTION, exprCollation(), exprType(), exprTypmod(), InvalidOid, isCompositeType(), JS_QUOTES_UNSPEC, JSON_BEHAVIOR_ERROR, JSW_UNSPEC, JsonTableParseContext::jt, JTC_EXISTS, JTC_FOR_ORDINALITY, JTC_FORMATTED, JTC_NESTED, JTC_REGULAR, lappend(), lappend_int(), lappend_oid(), lfirst, list_length(), JsonTableColumn::location, makeJsonTablePathScan(), makeNode, makeString(), JsonTableColumn::name, JsonTable::on_error, parser_errposition(), JsonTableParseContext::pstate, pstrdup(), JsonTableColumn::quotes, JsonTableParseContext::tf, transformExpr(), transformJsonTableColumn(), transformJsonTableNestedColumns(), CaseTestExpr::typeId, JsonTableColumn::typeName, typenameTypeIdAndMod(), and JsonTableColumn::wrapper.

Referenced by transformJsonTable(), and transformJsonTableNestedColumns().

transformJsonTableNestedColumns()

static JsonTablePlan * transformJsonTableNestedColumns ( JsonTableParseContext *  cxt, List *  passingArgs, List *  columns  )

static

Definition at line 452 of file parse_jsontable.c.

{
    JsonTablePlan *plan = NULL;
    ListCell   *lc;
 
    /*
     * If there are multiple NESTED COLUMNS clauses in 'columns', their
     * respective plans will be combined using a "sibling join" plan, which
     * effectively does a UNION of the sets of rows coming from each nested
     * plan.
     */
    foreach(lc, columns)
    {
        JsonTableColumn *jtc = castNode(JsonTableColumn, lfirst(lc));
        JsonTablePlan *nested;
 
        if (jtc->coltype != JTC_NESTED)
            continue;
 
        if (jtc->pathspec->name == NULL)
            jtc->pathspec->name = generateJsonTablePathName(cxt);
 
        nested = transformJsonTableColumns(cxt, jtc->columns, passingArgs,
                                           jtc->pathspec);
 
        if (plan)
            plan = makeJsonTableSiblingJoin(plan, nested);
        else
            plan = nested;
    }
 
    return plan;
}

References castNode, JsonTableColumn::coltype, JsonTableColumn::columns, generateJsonTablePathName(), JTC_NESTED, lfirst, makeJsonTableSiblingJoin(), JsonTablePathSpec::name, JsonTableColumn::pathspec, plan, and transformJsonTableColumns().

Referenced by transformJsonTableColumns().