enh(query): add derivative function selectivity

TD-17659

source/libs/function/src/builtins.c

@@ -2220,7 +2220,7 @@ const SBuiltinFuncDefinition funcMgtBuiltins[] = {
   {
     .name = "derivative",
     .type = FUNCTION_TYPE_DERIVATIVE,
-    .classification = FUNC_MGT_INDEFINITE_ROWS_FUNC | FUNC_MGT_TIMELINE_FUNC | FUNC_MGT_IMPLICIT_TS_FUNC,
+    .classification = FUNC_MGT_INDEFINITE_ROWS_FUNC | FUNC_MGT_SELECT_FUNC | FUNC_MGT_TIMELINE_FUNC | FUNC_MGT_IMPLICIT_TS_FUNC,
     .translateFunc = translateDerivative,
     .getEnvFunc   = getDerivativeFuncEnv,
     .initFunc     = derivativeFuncSetup,

source/libs/function/src/builtinsimpl.c

@@ -5767,6 +5767,12 @@ int32_t derivativeFunction(SqlFunctionCtx* pCtx) {
           if (pTsOutput != NULL) {
             colDataAppendInt64(pTsOutput, pos, &tsList[i]);
           }
+
+          // handle selectivity
+          if (pCtx->subsidiaries.num > 0) {
+            appendSelectivityValue(pCtx, i, pos);
+          }
+
           numOfElems++;
         }
       }
@@ -5799,6 +5805,12 @@ int32_t derivativeFunction(SqlFunctionCtx* pCtx) {
           if (pTsOutput != NULL) {
             colDataAppendInt64(pTsOutput, pos, &pDerivInfo->prevTs);
           }
+
+          // handle selectivity
+          if (pCtx->subsidiaries.num > 0) {
+            appendSelectivityValue(pCtx, i, pos);
+          }
+
           numOfElems++;
         }
       }