From 9ca819aa69330d6d368912a4ed29ea8e7c8ca6b0 Mon Sep 17 00:00:00 2001
From: Ganlin Zhao <ganlinzhao@hotmail.com>
Date: Tue, 28 Jun 2022 14:08:34 +0800
Subject: [PATCH] enh(query): last function support selectivity

---
 source/libs/function/src/builtins.c     |  8 ++++----
 source/libs/function/src/builtinsimpl.c | 22 ++++++++++++++++++----
 2 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/source/libs/function/src/builtins.c b/source/libs/function/src/builtins.c
index a6fa8ea721..e1e8a686aa 100644
--- a/source/libs/function/src/builtins.c
+++ b/source/libs/function/src/builtins.c
@@ -1914,7 +1914,7 @@ const SBuiltinFuncDefinition funcMgtBuiltins[] = {
   {
     .name = "_first_merge",
     .type = FUNCTION_TYPE_FIRST_MERGE,
-    .classification = FUNC_MGT_AGG_FUNC | FUNC_MGT_MULTI_RES_FUNC | FUNC_MGT_TIMELINE_FUNC,
+    .classification = FUNC_MGT_AGG_FUNC | FUNC_MGT_SELECT_FUNC | FUNC_MGT_MULTI_RES_FUNC | FUNC_MGT_TIMELINE_FUNC,
     .translateFunc = translateFirstLastMerge,
     .getEnvFunc   = getFirstLastFuncEnv,
     .initFunc     = functionSetup,
@@ -1925,7 +1925,7 @@ const SBuiltinFuncDefinition funcMgtBuiltins[] = {
   {
     .name = "last",
     .type = FUNCTION_TYPE_LAST,
-    .classification = FUNC_MGT_AGG_FUNC | FUNC_MGT_MULTI_RES_FUNC | FUNC_MGT_TIMELINE_FUNC,
+    .classification = FUNC_MGT_AGG_FUNC | FUNC_MGT_SELECT_FUNC | FUNC_MGT_MULTI_RES_FUNC | FUNC_MGT_TIMELINE_FUNC,
     .translateFunc = translateFirstLast,
     .getEnvFunc   = getFirstLastFuncEnv,
     .initFunc     = functionSetup,
@@ -1938,7 +1938,7 @@ const SBuiltinFuncDefinition funcMgtBuiltins[] = {
   {
     .name = "_last_partial",
     .type = FUNCTION_TYPE_LAST_PARTIAL,
-    .classification = FUNC_MGT_AGG_FUNC | FUNC_MGT_MULTI_RES_FUNC | FUNC_MGT_TIMELINE_FUNC,
+    .classification = FUNC_MGT_AGG_FUNC | FUNC_MGT_SELECT_FUNC | FUNC_MGT_MULTI_RES_FUNC | FUNC_MGT_TIMELINE_FUNC,
     .translateFunc = translateFirstLastPartial,
     .getEnvFunc   = getFirstLastFuncEnv,
     .initFunc     = functionSetup,
@@ -1949,7 +1949,7 @@ const SBuiltinFuncDefinition funcMgtBuiltins[] = {
   {
     .name = "_last_merge",
     .type = FUNCTION_TYPE_LAST_MERGE,
-    .classification = FUNC_MGT_AGG_FUNC | FUNC_MGT_MULTI_RES_FUNC | FUNC_MGT_TIMELINE_FUNC,
+    .classification = FUNC_MGT_AGG_FUNC | FUNC_MGT_SELECT_FUNC | FUNC_MGT_MULTI_RES_FUNC | FUNC_MGT_TIMELINE_FUNC,
     .translateFunc = translateFirstLastMerge,
     .getEnvFunc   = getFirstLastFuncEnv,
     .initFunc     = functionSetup,
diff --git a/source/libs/function/src/builtinsimpl.c b/source/libs/function/src/builtinsimpl.c
index d5e5b38558..eb0c444776 100644
--- a/source/libs/function/src/builtinsimpl.c
+++ b/source/libs/function/src/builtinsimpl.c
@@ -2593,8 +2593,15 @@ int32_t lastFunction(SqlFunctionCtx* pCtx) {
         }
         memcpy(pInfo->buf, data, bytes);
         *(TSKEY*)(pInfo->buf + bytes) = cts;
-        //        DO_UPDATE_TAG_COLUMNS(pCtx, ts);
-        pInfo->hasResult = true;
+        //handle selectivity
+        STuplePos* pTuplePos = (STuplePos*)(pInfo->buf + bytes + sizeof(TSKEY));
+        if (!pInfo->hasResult) {
+          saveTupleData(pCtx, i, pCtx->pSrcBlock, pTuplePos);
+          pInfo->hasResult = true;
+        } else {
+          copyTupleData(pCtx, i, pCtx->pSrcBlock, pTuplePos);
+        }
+        //DO_UPDATE_TAG_COLUMNS(pCtx, ts);
         pResInfo->numOfRes = 1;
       }
       break;
@@ -2616,9 +2623,16 @@ int32_t lastFunction(SqlFunctionCtx* pCtx) {
         }
         memcpy(pInfo->buf, data, bytes);
         *(TSKEY*)(pInfo->buf + bytes) = cts;
-        pInfo->hasResult = true;
+        //handle selectivity
+        STuplePos* pTuplePos = (STuplePos*)(pInfo->buf + bytes + sizeof(TSKEY));
+        if (!pInfo->hasResult) {
+          saveTupleData(pCtx, i, pCtx->pSrcBlock, pTuplePos);
+          pInfo->hasResult = true;
+        } else {
+          copyTupleData(pCtx, i, pCtx->pSrcBlock, pTuplePos);
+        }
         pResInfo->numOfRes = 1;
-        //        DO_UPDATE_TAG_COLUMNS(pCtx, ts);
+        //DO_UPDATE_TAG_COLUMNS(pCtx, ts);
       }
       break;
     }