TDengine/include/libs/nodes/querynodes.h
Jinqing Kuang 1ccaaf75bd fix(query)[TS-5443]. Fix invalid key in ORDER BY within subqueries
Resolved an issue where an ORDER BY alias in subqueries failed to
convert to the expected ColumnNode when the corresponding column
could be omitted. Updated the conversion logic to handle this case
correctly and ensure proper query execution.
2024-09-20 14:44:30 +08:00

675 lines
20 KiB
C

/*
* Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
*
* This program is free software: you can use, redistribute, and/or modify
* it under the terms of the GNU Affero General Public License, version 3
* or later ("AGPL"), as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _TD_QUERY_NODES_H_
#define _TD_QUERY_NODES_H_
#ifdef __cplusplus
extern "C" {
#endif
#include "nodes.h"
#include "tmsg.h"
#include "tvariant.h"
#include "tsimplehash.h"
#define TABLE_TOTAL_COL_NUM(pMeta) ((pMeta)->tableInfo.numOfColumns + (pMeta)->tableInfo.numOfTags)
#define TABLE_META_SIZE(pMeta) \
(NULL == (pMeta) ? 0 : (sizeof(STableMeta) + TABLE_TOTAL_COL_NUM((pMeta)) * sizeof(SSchema)))
#define VGROUPS_INFO_SIZE(pInfo) \
(NULL == (pInfo) ? 0 : (sizeof(SVgroupsInfo) + (pInfo)->numOfVgroups * sizeof(SVgroupInfo)))
typedef struct SAssociationNode {
SNode** pPlace;
SNode* pAssociationNode;
} SAssociationNode;
typedef struct SRawExprNode {
ENodeType nodeType;
char* p;
uint32_t n;
SNode* pNode;
bool isPseudoColumn;
} SRawExprNode;
typedef struct SDataType {
uint8_t type;
uint8_t precision;
uint8_t scale;
int32_t bytes;
} SDataType;
typedef struct SExprNode {
ENodeType type;
SDataType resType;
char aliasName[TSDB_COL_NAME_LEN];
char userAlias[TSDB_COL_NAME_LEN];
SArray* pAssociation;
bool asAlias;
bool asParam;
bool asPosition;
int32_t projIdx;
} SExprNode;
typedef enum EColumnType {
COLUMN_TYPE_COLUMN = 1,
COLUMN_TYPE_TAG,
COLUMN_TYPE_TBNAME,
COLUMN_TYPE_WINDOW_START,
COLUMN_TYPE_WINDOW_END,
COLUMN_TYPE_WINDOW_DURATION,
COLUMN_TYPE_GROUP_KEY
} EColumnType;
typedef struct SColumnNode {
SExprNode node; // QUERY_NODE_COLUMN
uint64_t tableId;
int8_t tableType;
col_id_t colId;
uint16_t projIdx; // the idx in project list, start from 1
EColumnType colType; // column or tag
bool hasIndex;
bool isPrimTs;
char dbName[TSDB_DB_NAME_LEN];
char tableName[TSDB_TABLE_NAME_LEN];
char tableAlias[TSDB_TABLE_NAME_LEN];
char colName[TSDB_COL_NAME_LEN];
int16_t dataBlockId;
int16_t slotId;
int16_t numOfPKs;
bool tableHasPk;
bool isPk;
int32_t projRefIdx;
int32_t resIdx;
} SColumnNode;
typedef struct SColumnRefNode {
ENodeType type;
SDataType resType;
char colName[TSDB_COL_NAME_LEN];
} SColumnRefNode;
typedef struct STargetNode {
ENodeType type;
int16_t dataBlockId;
int16_t slotId;
SNode* pExpr;
} STargetNode;
#define VALUE_FLAG_IS_DURATION (1 << 0)
#define VALUE_FLAG_IS_TIME_OFFSET (1 << 1)
#define IS_DURATION_VAL(_flag) ((_flag) & VALUE_FLAG_IS_DURATION)
#define IS_TIME_OFFSET_VAL(_flag) ((_flag) & VALUE_FLAG_IS_TIME_OFFSET)
typedef struct SValueNode {
SExprNode node; // QUERY_NODE_VALUE
char* literal;
int32_t flag;
bool translate;
bool notReserved;
bool isNull;
int16_t placeholderNo;
union {
bool b;
int64_t i;
uint64_t u;
double d;
char* p;
} datum;
int64_t typeData;
int8_t unit;
} SValueNode;
typedef struct SLeftValueNode {
ENodeType type;
} SLeftValueNode;
typedef enum EHintOption {
HINT_NO_BATCH_SCAN = 1,
HINT_BATCH_SCAN,
HINT_SORT_FOR_GROUP,
HINT_PARTITION_FIRST,
HINT_PARA_TABLES_SORT,
HINT_SMALLDATA_TS_SORT,
HINT_HASH_JOIN,
HINT_SKIP_TSMA,
} EHintOption;
typedef struct SHintNode {
ENodeType type;
EHintOption option;
void* value;
} SHintNode;
typedef struct SOperatorNode {
SExprNode node; // QUERY_NODE_OPERATOR
EOperatorType opType;
SNode* pLeft;
SNode* pRight;
} SOperatorNode;
typedef struct SLogicConditionNode {
SExprNode node; // QUERY_NODE_LOGIC_CONDITION
ELogicConditionType condType;
SNodeList* pParameterList;
} SLogicConditionNode;
typedef struct SNodeListNode {
SExprNode node; // QUERY_NODE_NODE_LIST
SNodeList* pNodeList;
} SNodeListNode;
typedef enum ETrimType {
TRIM_TYPE_LEADING = 1,
TRIM_TYPE_TRAILING,
TRIM_TYPE_BOTH,
} ETrimType;
typedef struct SFunctionNode {
SExprNode node; // QUERY_NODE_FUNCTION
char functionName[TSDB_FUNC_NAME_LEN];
int32_t funcId;
int32_t funcType;
SNodeList* pParameterList;
int32_t udfBufSize;
bool hasPk;
int32_t pkBytes;
bool hasOriginalFunc;
int32_t originalFuncId;
ETrimType trimType;
bool hasSMA;
bool dual; // whether select stmt without from stmt, true for without.
} SFunctionNode;
typedef struct STableNode {
SExprNode node;
char dbName[TSDB_DB_NAME_LEN];
char tableName[TSDB_TABLE_NAME_LEN];
char tableAlias[TSDB_TABLE_NAME_LEN];
uint8_t precision;
bool singleTable;
} STableNode;
struct STableMeta;
typedef struct STsmaTargetCTbInfo {
char tableName[TSDB_TABLE_NAME_LEN]; // child table or normal table name
uint64_t uid;
} STsmaTargetTbInfo;
typedef struct SRealTableNode {
STableNode table; // QUERY_NODE_REAL_TABLE
struct STableMeta* pMeta;
SVgroupsInfo* pVgroupList;
char qualDbName[TSDB_DB_NAME_LEN]; // SHOW qualDbName.TABLES
double ratio;
SArray* pSmaIndexes;
int8_t cacheLastMode;
int8_t stbRewrite;
SArray* pTsmas;
SArray* tsmaTargetTbVgInfo; // SArray<SVgroupsInfo*>, used for child table or normal table only
SArray* tsmaTargetTbInfo; // SArray<STsmaTargetTbInfo>, used for child table or normal table only
} SRealTableNode;
typedef struct STempTableNode {
STableNode table; // QUERY_NODE_TEMP_TABLE
SNode* pSubquery;
} STempTableNode;
typedef struct SViewNode {
STableNode table; // QUERY_NODE_REAL_TABLE
struct STableMeta* pMeta;
SVgroupsInfo* pVgroupList;
char qualDbName[TSDB_DB_NAME_LEN]; // SHOW qualDbName.TABLES
double ratio;
SArray* pSmaIndexes;
int8_t cacheLastMode;
} SViewNode;
#define JOIN_JLIMIT_MAX_VALUE 1024
#define IS_INNER_NONE_JOIN(_type, _stype) ((_type) == JOIN_TYPE_INNER && (_stype) == JOIN_STYPE_NONE)
#define IS_SEMI_JOIN(_stype) ((_stype) == JOIN_STYPE_SEMI)
#define IS_WINDOW_JOIN(_stype) ((_stype) == JOIN_STYPE_WIN)
#define IS_ASOF_JOIN(_stype) ((_stype) == JOIN_STYPE_ASOF)
typedef enum EJoinType {
JOIN_TYPE_INNER = 0,
JOIN_TYPE_LEFT,
JOIN_TYPE_RIGHT,
JOIN_TYPE_FULL,
JOIN_TYPE_MAX_VALUE
} EJoinType;
typedef enum EJoinSubType {
JOIN_STYPE_NONE = 0,
JOIN_STYPE_OUTER,
JOIN_STYPE_SEMI,
JOIN_STYPE_ANTI,
JOIN_STYPE_ASOF,
JOIN_STYPE_WIN,
JOIN_STYPE_MAX_VALUE
} EJoinSubType;
typedef enum EJoinAlgorithm {
JOIN_ALGO_UNKNOWN = 0,
JOIN_ALGO_MERGE,
JOIN_ALGO_HASH,
} EJoinAlgorithm;
typedef enum EDynQueryType {
DYN_QTYPE_STB_HASH = 1,
} EDynQueryType;
typedef struct SJoinTableNode {
STableNode table; // QUERY_NODE_JOIN_TABLE
EJoinType joinType;
EJoinSubType subType;
SNode* pWindowOffset;
SNode* pJLimit;
SNode* addPrimCond;
bool hasSubQuery;
bool isLowLevelJoin;
SNode* pLeft;
SNode* pRight;
SNode* pOnCond;
} SJoinTableNode;
typedef enum EGroupingSetType { GP_TYPE_NORMAL = 1 } EGroupingSetType;
typedef struct SGroupingSetNode {
ENodeType type; // QUERY_NODE_GROUPING_SET
EGroupingSetType groupingSetType;
SNodeList* pParameterList;
} SGroupingSetNode;
typedef enum EOrder { ORDER_ASC = 1, ORDER_DESC } EOrder;
typedef enum ENullOrder { NULL_ORDER_DEFAULT = 1, NULL_ORDER_FIRST, NULL_ORDER_LAST } ENullOrder;
typedef struct SOrderByExprNode {
ENodeType type; // QUERY_NODE_ORDER_BY_EXPR
SNode* pExpr;
EOrder order;
ENullOrder nullOrder;
} SOrderByExprNode;
typedef struct SLimitNode {
ENodeType type; // QUERY_NODE_LIMIT
int64_t limit;
int64_t offset;
} SLimitNode;
typedef struct SStateWindowNode {
ENodeType type; // QUERY_NODE_STATE_WINDOW
SNode* pCol; // timestamp primary key
SNode* pExpr;
} SStateWindowNode;
typedef struct SSessionWindowNode {
ENodeType type; // QUERY_NODE_SESSION_WINDOW
SColumnNode* pCol; // timestamp primary key
SValueNode* pGap; // gap between two session window(in microseconds)
} SSessionWindowNode;
typedef struct SIntervalWindowNode {
ENodeType type; // QUERY_NODE_INTERVAL_WINDOW
SNode* pCol; // timestamp primary key
SNode* pInterval; // SValueNode
SNode* pOffset; // SValueNode
SNode* pSliding; // SValueNode
SNode* pFill;
} SIntervalWindowNode;
typedef struct SEventWindowNode {
ENodeType type; // QUERY_NODE_EVENT_WINDOW
SNode* pCol; // timestamp primary key
SNode* pStartCond;
SNode* pEndCond;
} SEventWindowNode;
typedef struct SCountWindowNode {
ENodeType type; // QUERY_NODE_EVENT_WINDOW
SNode* pCol; // timestamp primary key
int64_t windowCount;
int64_t windowSliding;
} SCountWindowNode;
typedef enum EFillMode {
FILL_MODE_NONE = 1,
FILL_MODE_VALUE,
FILL_MODE_VALUE_F,
FILL_MODE_PREV,
FILL_MODE_NULL,
FILL_MODE_NULL_F,
FILL_MODE_LINEAR,
FILL_MODE_NEXT
} EFillMode;
typedef enum ETimeLineMode {
TIME_LINE_NONE = 1,
TIME_LINE_BLOCK,
TIME_LINE_MULTI,
TIME_LINE_GLOBAL,
} ETimeLineMode;
typedef enum EShowKind {
SHOW_KIND_ALL = 1,
SHOW_KIND_TABLES_NORMAL,
SHOW_KIND_TABLES_CHILD,
SHOW_KIND_DATABASES_USER,
SHOW_KIND_DATABASES_SYSTEM
} EShowKind;
typedef struct SFillNode {
ENodeType type; // QUERY_NODE_FILL
EFillMode mode;
SNode* pValues; // SNodeListNode
SNode* pWStartTs; // _wstart pseudo column
STimeWindow timeRange;
} SFillNode;
typedef struct SWhenThenNode {
SExprNode node; // QUERY_NODE_WHEN_THEN
SNode* pWhen;
SNode* pThen;
} SWhenThenNode;
typedef struct SCaseWhenNode {
SExprNode node; // QUERY_NODE_CASE_WHEN
SNode* pCase;
SNode* pElse;
SNodeList* pWhenThenList;
} SCaseWhenNode;
typedef struct SWindowOffsetNode {
ENodeType type; // QUERY_NODE_WINDOW_OFFSET
SNode* pStartOffset; // SValueNode
SNode* pEndOffset; // SValueNode
} SWindowOffsetNode;
typedef struct SSelectStmt {
ENodeType type; // QUERY_NODE_SELECT_STMT
bool isDistinct;
SNodeList* pProjectionList;
SNode* pFromTable;
SNode* pWhere;
SNodeList* pPartitionByList;
SNodeList* pTags; // for create stream
SNode* pSubtable; // for create stream
SNode* pWindow;
SNodeList* pGroupByList; // SGroupingSetNode
SNode* pHaving;
SNode* pRange;
SNode* pEvery;
SNode* pFill;
SNodeList* pOrderByList; // SOrderByExprNode
SLimitNode* pLimit;
SLimitNode* pSlimit;
STimeWindow timeRange;
SNodeList* pHint;
char stmtName[TSDB_TABLE_NAME_LEN];
uint8_t precision;
int32_t selectFuncNum;
int32_t returnRows; // EFuncReturnRows
ETimeLineMode timeLineCurMode;
ETimeLineMode timeLineResMode;
int32_t lastProcessByRowFuncId;
bool timeLineFromOrderBy;
bool isEmptyResult;
bool isSubquery;
bool hasAggFuncs;
bool hasRepeatScanFuncs;
bool hasIndefiniteRowsFunc;
bool hasMultiRowsFunc;
bool hasSelectFunc;
bool hasSelectValFunc;
bool hasOtherVectorFunc;
bool hasUniqueFunc;
bool hasTailFunc;
bool hasInterpFunc;
bool hasInterpPseudoColFunc;
bool hasLastRowFunc;
bool hasLastFunc;
bool hasTimeLineFunc;
bool hasCountFunc;
bool hasUdaf;
bool hasStateKey;
bool onlyHasKeepOrderFunc;
bool groupSort;
bool tagScan;
bool joinContains;
} SSelectStmt;
typedef enum ESetOperatorType { SET_OP_TYPE_UNION_ALL = 1, SET_OP_TYPE_UNION } ESetOperatorType;
typedef struct SSetOperator {
ENodeType type; // QUERY_NODE_SET_OPERATOR
ESetOperatorType opType;
SNodeList* pProjectionList;
SNode* pLeft;
SNode* pRight;
SNodeList* pOrderByList; // SOrderByExprNode
SNode* pLimit;
char stmtName[TSDB_TABLE_NAME_LEN];
uint8_t precision;
ETimeLineMode timeLineResMode;
bool timeLineFromOrderBy;
bool joinContains;
} SSetOperator;
typedef enum ESqlClause {
SQL_CLAUSE_FROM = 1,
SQL_CLAUSE_WHERE,
SQL_CLAUSE_PARTITION_BY,
SQL_CLAUSE_WINDOW,
SQL_CLAUSE_FILL,
SQL_CLAUSE_GROUP_BY,
SQL_CLAUSE_HAVING,
SQL_CLAUSE_DISTINCT,
SQL_CLAUSE_SELECT,
SQL_CLAUSE_ORDER_BY
} ESqlClause;
typedef struct SDeleteStmt {
ENodeType type; // QUERY_NODE_DELETE_STMT
SNode* pFromTable; // FROM clause
SNode* pWhere; // WHERE clause
SNode* pCountFunc; // count the number of rows affected
SNode* pFirstFunc; // the start timestamp when the data was actually deleted
SNode* pLastFunc; // the end timestamp when the data was actually deleted
SNode* pTagCond; // pWhere divided into pTagCond and timeRange
STimeWindow timeRange;
uint8_t precision;
bool deleteZeroRows;
} SDeleteStmt;
typedef struct SInsertStmt {
ENodeType type; // QUERY_NODE_INSERT_STMT
SNode* pTable;
SNodeList* pCols;
SNode* pQuery;
uint8_t precision;
} SInsertStmt;
typedef struct SVgDataBlocks {
SVgroupInfo vg;
int32_t numOfTables; // number of tables in current submit block
uint32_t size;
void* pData; // SSubmitReq + SSubmitBlk + ...
} SVgDataBlocks;
typedef void (*FFreeTableBlockHash)(SHashObj*);
typedef void (*FFreeVgourpBlockArray)(SArray*);
struct SStbRowsDataContext;
typedef void (*FFreeStbRowsDataContext)(struct SStbRowsDataContext*);
struct SCreateTbInfo;
struct SParseFileContext;
typedef void (*FDestroyParseFileContext)(struct SParseFileContext**);
typedef struct SVnodeModifyOpStmt {
ENodeType nodeType;
ENodeType sqlNodeType;
SArray* pDataBlocks; // data block for each vgroup, SArray<SVgDataBlocks*>.
uint32_t insertType; // insert data from [file|sql statement| bound statement]
const char* pSql; // current sql statement position
int32_t totalRowsNum;
int32_t totalTbNum;
SName targetTableName;
SName usingTableName;
const char* pBoundCols;
struct STableMeta* pTableMeta;
SNode* pTagCond;
SArray* pTableTag;
SHashObj* pVgroupsHashObj; // SHashObj<vgId, SVgInfo>
SHashObj* pTableBlockHashObj; // SHashObj<tuid, STableDataCxt*>
SHashObj* pSubTableHashObj; // SHashObj<table_name, STableMeta*>
SHashObj* pTableNameHashObj; // set of table names for refreshing meta, sync mode
SHashObj* pDbFNameHashObj; // set of db names for refreshing meta, sync mode
SHashObj* pTableCxtHashObj; // temp SHashObj<tuid, STableDataCxt*> for single request
SArray* pVgDataBlocks; // SArray<SVgroupDataCxt*>
SVCreateTbReq* pCreateTblReq;
TdFilePtr fp;
FFreeTableBlockHash freeHashFunc;
FFreeVgourpBlockArray freeArrayFunc;
bool usingTableProcessing;
bool fileProcessing;
bool stbSyntax;
struct SStbRowsDataContext* pStbRowsCxt;
FFreeStbRowsDataContext freeStbRowsCxtFunc;
struct SCreateTbInfo* pCreateTbInfo;
struct SParseFileContext* pParFileCxt;
FDestroyParseFileContext destroyParseFileCxt;
} SVnodeModifyOpStmt;
typedef struct SExplainOptions {
ENodeType type;
bool verbose;
double ratio;
} SExplainOptions;
typedef struct SExplainStmt {
ENodeType type;
bool analyze;
SExplainOptions* pOptions;
SNode* pQuery;
} SExplainStmt;
typedef struct SCmdMsgInfo {
int16_t msgType;
SEpSet epSet;
void* pMsg;
int32_t msgLen;
} SCmdMsgInfo;
typedef enum EQueryExecMode {
QUERY_EXEC_MODE_LOCAL = 1,
QUERY_EXEC_MODE_RPC,
QUERY_EXEC_MODE_SCHEDULE,
QUERY_EXEC_MODE_EMPTY_RESULT
} EQueryExecMode;
typedef enum EQueryExecStage {
QUERY_EXEC_STAGE_PARSE = 1,
QUERY_EXEC_STAGE_ANALYSE,
QUERY_EXEC_STAGE_SCHEDULE,
QUERY_EXEC_STAGE_END
} EQueryExecStage;
typedef struct SQuery {
ENodeType type;
EQueryExecStage execStage;
EQueryExecMode execMode;
bool haveResultSet;
SNode* pPrevRoot;
SNode* pRoot;
SNode* pPostRoot;
int32_t numOfResCols;
SSchema* pResSchema;
int8_t precision;
SCmdMsgInfo* pCmdMsg;
int32_t msgType;
SArray* pTargetTableList;
SArray* pTableList;
SArray* pDbList;
bool showRewrite;
int32_t placeholderNum;
SArray* pPlaceholderValues;
SNode* pPrepareRoot;
bool stableQuery;
} SQuery;
void nodesWalkSelectStmtImpl(SSelectStmt* pSelect, ESqlClause clause, FNodeWalker walker, void* pContext);
void nodesWalkSelectStmt(SSelectStmt* pSelect, ESqlClause clause, FNodeWalker walker, void* pContext);
void nodesRewriteSelectStmt(SSelectStmt* pSelect, ESqlClause clause, FNodeRewriter rewriter, void* pContext);
typedef enum ECollectColType { COLLECT_COL_TYPE_COL = 1, COLLECT_COL_TYPE_TAG, COLLECT_COL_TYPE_ALL } ECollectColType;
int32_t nodesCollectColumns(SSelectStmt* pSelect, ESqlClause clause, const char* pTableAlias, ECollectColType type,
SNodeList** pCols);
int32_t nodesCollectColumnsExt(SSelectStmt* pSelect, ESqlClause clause, SSHashObj* pMultiTableAlias, ECollectColType type,
SNodeList** pCols);
int32_t nodesCollectColumnsFromNode(SNode* node, const char* pTableAlias, ECollectColType type, SNodeList** pCols);
typedef bool (*FFuncClassifier)(int32_t funcId);
int32_t nodesCollectFuncs(SSelectStmt* pSelect, ESqlClause clause, char* tableAlias, FFuncClassifier classifier, SNodeList** pFuncs);
int32_t nodesCollectSelectFuncs(SSelectStmt* pSelect, ESqlClause clause, char* tableAlias, FFuncClassifier classifier, SNodeList* pFuncs);
int32_t nodesCollectSpecialNodes(SSelectStmt* pSelect, ESqlClause clause, ENodeType type, SNodeList** pNodes);
bool nodesIsExprNode(const SNode* pNode);
bool nodesIsUnaryOp(const SOperatorNode* pOp);
bool nodesIsArithmeticOp(const SOperatorNode* pOp);
bool nodesIsComparisonOp(const SOperatorNode* pOp);
bool nodesIsJsonOp(const SOperatorNode* pOp);
bool nodesIsRegularOp(const SOperatorNode* pOp);
bool nodesIsMatchRegularOp(const SOperatorNode* pOp);
bool nodesIsBitwiseOp(const SOperatorNode* pOp);
bool nodesExprHasColumn(SNode* pNode);
bool nodesExprsHasColumn(SNodeList* pList);
void* nodesGetValueFromNode(SValueNode* pNode);
int32_t nodesSetValueNodeValue(SValueNode* pNode, void* value);
char* nodesGetStrValueFromNode(SValueNode* pNode);
int32_t nodesValueNodeToVariant(const SValueNode* pNode, SVariant* pVal);
int32_t nodesMakeValueNodeFromString(char* literal, SValueNode** ppValNode);
int32_t nodesMakeValueNodeFromBool(bool b, SValueNode** ppValNode);
int32_t nodesMakeValueNodeFromInt32(int32_t value, SNode** ppNode);
char* nodesGetFillModeString(EFillMode mode);
int32_t nodesMergeConds(SNode** pDst, SNodeList** pSrc);
const char* operatorTypeStr(EOperatorType type);
const char* logicConditionTypeStr(ELogicConditionType type);
bool nodesIsStar(SNode* pNode);
bool nodesIsTableStar(SNode* pNode);
char* getJoinTypeString(EJoinType type);
char* getJoinSTypeString(EJoinSubType type);
char* getFullJoinTypeString(EJoinType type, EJoinSubType stype);
int32_t mergeJoinConds(SNode** ppDst, SNode** ppSrc);
#ifdef __cplusplus
}
#endif
#endif /*_TD_QUERY_NODES_H_*/