支持keep函数

src/include/executor/node/nodeAgg.h

@@ -195,6 +195,8 @@ typedef struct AggStatePerAggData {
     ProjectionInfo *evalproj;	/* projection machinery */
     ProjectionInfo *combinedproj; /* projection machinery */
     TupleTableSlot *evalslot;	/* current input tuple */
+    TupleTableSlot **keep_slot;
+    bool is_keep;
 } AggStatePerAggData;
 
 /*

src/include/miscadmin.h

@@ -161,6 +161,7 @@ extern const uint32 MINMAXEXPR_CMPTYPE_VERSION_NUM;
 extern const uint32 CHARBYTE_SEMANTIC_VERSION_NUMBER;
 extern const uint32 APPLY_JOIN_VERSION_NUMBER;
 extern const uint32 PUBLIC_SYNONYM_VERSION_NUMBER;
+extern const uint32 KEEP_FUNC_VERSION_NUMBER;
 
 extern void register_backend_version(uint32 backend_version);
 extern bool contain_backend_version(uint32 version_number);

src/include/nodes/execnodes.h

@@ -909,6 +909,8 @@ typedef struct WindowFuncExprState {
     // Vectorized aggregation fields
     //
     ScalarVector* m_resultVector;
+    List *keep_args;
+    bool keep_first;
 } WindowFuncExprState;
 
 

src/include/nodes/nodes.h

@@ -915,7 +915,8 @@ typedef enum NodeTag {
     T_RotateClause = 6000,
     T_UnrotateClause,
     T_RotateInCell,
-    T_UnrotateInCell
+    T_UnrotateInCell,
+    T_KeepClause
 
 } NodeTag;
 

src/include/nodes/parsenodes_common.h

@@ -1702,6 +1702,14 @@ typedef struct CommonTableExpr {
     StartWithOptions    *swoptions; /* START WITH CONNECT BY options */
 } CommonTableExpr;
 
+typedef struct KeepClause
+{
+    NodeTag type;
+    bool rank_first;
+    List *keep_order;
+    int location;
+} KeepClause;
+
 /*
  * FuncCall - a function or aggregate invocation
  *
@@ -1719,6 +1727,7 @@ typedef struct FuncCall {
     List *args;      /* the arguments (list of exprs) */
     List *agg_order; /* ORDER BY (list of SortBy) */
     Node *agg_filter;
+    KeepClause *aggKeep;
     bool agg_within_group;
     bool agg_star;          /* argument was really '*' */
     bool agg_distinct;      /* arguments were labeled DISTINCT */

src/include/nodes/primnodes.h

@@ -295,6 +295,8 @@ typedef struct Aggref {
     List* args;            /* arguments and sort expressions */
     List* aggorder;        /* ORDER BY (list of SortGroupClause) */
     List* aggdistinct;     /* DISTINCT (list of SortGroupClause) */
+    bool aggiskeep;
+    bool aggkpfirst;
     bool aggstar;          /* TRUE if argument list was really '*' */
     bool aggvariadic;      /* true if variadic arguments have been
                             * combined into an array last argument */
@@ -359,6 +361,9 @@ typedef struct WindowFunc {
     bool winstar;    /* TRUE if argument list was really '*' */
     bool winagg;     /* is function a simple aggregate? */
     int location;    /* token location, or -1 if unknown */
+    List* keep_args;
+    List* winkporder;
+    bool winkpfirst;
 #ifdef USE_SPQ
     bool windistinct;	/* TRUE if it's agg(DISTINCT ...) */
 #endif

src/include/parser/kwlist.h

@@ -205,6 +205,7 @@ PG_KEYWORD("delimiter", DELIMITER, UNRESERVED_KEYWORD)
 PG_KEYWORD("delimiters", DELIMITERS, UNRESERVED_KEYWORD)
 PG_KEYWORD("delta", DELTA, UNRESERVED_KEYWORD)
 PG_KEYWORD("deltamerge", DELTAMERGE, TYPE_FUNC_NAME_KEYWORD)
+PG_KEYWORD("dense_rank", DENSE_RANK, UNRESERVED_KEYWORD)
 PG_KEYWORD("desc", DESC, RESERVED_KEYWORD)
 PG_KEYWORD("deterministic", DETERMINISTIC, UNRESERVED_KEYWORD)
 PG_KEYWORD("diagnostics", DIAGNOSTICS, UNRESERVED_KEYWORD)
@@ -352,6 +353,7 @@ PG_KEYWORD("is", IS, RESERVED_KEYWORD)
 PG_KEYWORD("isnull", ISNULL, UNRESERVED_KEYWORD)
 PG_KEYWORD("isolation", ISOLATION, UNRESERVED_KEYWORD)
 PG_KEYWORD("join", JOIN, TYPE_FUNC_NAME_KEYWORD)
+PG_KEYWORD("keep", KEEP, UNRESERVED_KEYWORD)
 PG_KEYWORD("key", KEY, UNRESERVED_KEYWORD)
 PG_KEYWORD("key_path", KEY_PATH, UNRESERVED_KEYWORD)
 PG_KEYWORD("key_store", KEY_STORE, UNRESERVED_KEYWORD)

src/include/utils/tuplesort.h

@@ -190,5 +190,6 @@ extern void UpdateUniqueSQLSortStats(Tuplesortstate* state, TimestampTz* start_t
 extern int64 tuplesort_get_peak_memory(Tuplesortstate* state);
 
 extern void tuplesort_workerfinish(Sharedsort *shared);
-
+extern void* TuplesortGetSortkeys(Tuplesortstate* state);
+extern int TuplesortGetNsortkey(Tuplesortstate* state);
 #endif /* TUPLESORT_H */

src/include/windowapi.h

@@ -94,6 +94,13 @@ typedef struct WindowStatePerFuncData {
 
 } WindowStatePerFuncData;
 
+typedef struct KeepRank {
+    bool        keeptypeByVal;
+    bool        keepValueIsNull;
+    int16       keeptypeLen;
+    Datum       keepValue;
+    SortSupportData keepSort;
+} KeepRank;
 /*
  * For plain aggregate window functions, we also have one of these.
  */
@@ -136,6 +143,10 @@ typedef struct WindowStatePerAggData {
     bool transValueIsNull;
 
     bool noTransValue; /* true if transValue not set yet */
+    int         numKeepCols;
+    bool        keep_first;
+    bool        keep_init;
+    KeepRank* keepRank;
 } WindowStatePerAggData;
 
 #define PG_WINDOW_OBJECT() ((WindowObject)fcinfo->context)