Fixed a subtle bug in removing aliases (#8003)

Author: pavelvelikhov

ydb/library/yql/dq/opt/dq_opt_join_hypergraph.h

@@ -67,11 +67,11 @@ class TJoinHypergraph {
                 auto leftKey = left.AttributeName;
                 auto rightKey = right.AttributeName;
 
-                if (auto idx = leftKey.find_last_of('.') != TString::npos) {
+                if (auto idx = leftKey.find_last_of('.'); idx != TString::npos) {
                     leftKey =  leftKey.substr(idx+1);
                 }
 
-                if (auto idx = rightKey.find_last_of('.') != TString::npos) {
+                if (auto idx = rightKey.find_last_of('.'); idx != TString::npos) {
                     rightKey =  rightKey.substr(idx+1);
                 }
 

ydb/library/yql/dq/opt/dq_opt_stat.cpp

@@ -24,7 +24,7 @@ namespace {
 
 
     TString RemoveAliases(TString attributeName) {
-        if (auto idx = attributeName.find_last_of('.') != TString::npos) {
+        if (auto idx = attributeName.find_last_of('.'); idx != TString::npos) {
             return attributeName.substr(idx+1);
         }
         return attributeName;

ydb/library/yql/providers/dq/planner/execution_planner.cpp

@@ -42,7 +42,7 @@ using namespace Yql::DqsProto;
 
 namespace {
     TString RemoveAliases(TString attributeName) {
-        if (auto idx = attributeName.find_last_of('.') != TString::npos) {
+        if (auto idx = attributeName.find_last_of('.'); idx != TString::npos) {
             return attributeName.substr(idx+1);
         }
         return attributeName;