fix(plugin): MCOL-4942 No-table-SELECT now can return empty set (#3413)

The query like "SELECT 1 WHERE 1=0" was returning a row despite
unsatisfiable condition in WHERE. Now it returns an empty set.

Author: mariadb-SergeyZefirov

dbcon/joblist/jlf_tuplejoblist.cpp

@@ -4520,33 +4520,6 @@ void associateTupleJobSteps(JobStepVector& querySteps, JobStepVector& projectSte
     cout << endl;
   }
 
-  // @bug 2771, handle no table select query
-  if (jobInfo.tableList.empty())
-  {
-    makeNoTableJobStep(querySteps, projectSteps, deliverySteps, jobInfo);
-    return;
-  }
-
-  // Create a step vector for each table in the from clause.
-  TableInfoMap tableInfoMap;
-
-  for (uint64_t i = 0; i < jobInfo.tableList.size(); i++)
-  {
-    uint32_t tableUid = jobInfo.tableList[i];
-    tableInfoMap[tableUid] = TableInfo();
-    tableInfoMap[tableUid].fTableOid = jobInfo.keyInfo->tupleKeyVec[tableUid].fId;
-    tableInfoMap[tableUid].fName = jobInfo.keyInfo->keyName[tableUid];
-    tableInfoMap[tableUid].fAlias = jobInfo.keyInfo->tupleKeyVec[tableUid].fTable;
-    tableInfoMap[tableUid].fView = jobInfo.keyInfo->tupleKeyVec[tableUid].fView;
-    tableInfoMap[tableUid].fSchema = jobInfo.keyInfo->tupleKeyVec[tableUid].fSchema;
-    tableInfoMap[tableUid].fSubId = jobInfo.keyInfo->tupleKeyVec[tableUid].fSubId;
-    tableInfoMap[tableUid].fColsInColMap = jobInfo.columnMap[tableUid];
-  }
-
-  // Set of the columns being projected.
-  for (auto i = jobInfo.pjColList.begin(); i != jobInfo.pjColList.end(); i++)
-    jobInfo.returnColSet.insert(i->key);
-
   // Strip constantbooleanquerySteps
   for (uint64_t i = 0; i < querySteps.size();)
   {
@@ -4582,6 +4555,33 @@ void associateTupleJobSteps(JobStepVector& querySteps, JobStepVector& projectSte
     }
   }
 
+  // @bug 2771, handle no table select query
+  if (jobInfo.tableList.empty())
+  {
+    makeNoTableJobStep(querySteps, projectSteps, deliverySteps, jobInfo);
+    return;
+  }
+
+  // Create a step vector for each table in the from clause.
+  TableInfoMap tableInfoMap;
+
+  for (uint64_t i = 0; i < jobInfo.tableList.size(); i++)
+  {
+    uint32_t tableUid = jobInfo.tableList[i];
+    tableInfoMap[tableUid] = TableInfo();
+    tableInfoMap[tableUid].fTableOid = jobInfo.keyInfo->tupleKeyVec[tableUid].fId;
+    tableInfoMap[tableUid].fName = jobInfo.keyInfo->keyName[tableUid];
+    tableInfoMap[tableUid].fAlias = jobInfo.keyInfo->tupleKeyVec[tableUid].fTable;
+    tableInfoMap[tableUid].fView = jobInfo.keyInfo->tupleKeyVec[tableUid].fView;
+    tableInfoMap[tableUid].fSchema = jobInfo.keyInfo->tupleKeyVec[tableUid].fSchema;
+    tableInfoMap[tableUid].fSubId = jobInfo.keyInfo->tupleKeyVec[tableUid].fSubId;
+    tableInfoMap[tableUid].fColsInColMap = jobInfo.columnMap[tableUid];
+  }
+
+  // Set of the columns being projected.
+  for (auto i = jobInfo.pjColList.begin(); i != jobInfo.pjColList.end(); i++)
+    jobInfo.returnColSet.insert(i->key);
+
   // double check if the function join canditates are still there.
   JobStepVector steps = querySteps;
 

dbcon/joblist/tupleconstantstep.cpp

@@ -284,7 +284,9 @@ void TupleConstantStep::constructContanstRow(const JobInfo& jobInfo)
 void TupleConstantStep::run()
 {
   if (fInputJobStepAssociation.outSize() == 0)
+  {
     throw logic_error("No input data list for constant step.");
+  }
 
   fInputDL = fInputJobStepAssociation.outAt(0)->rowGroupDL();
 
@@ -585,7 +587,9 @@ void TupleConstantStep::formatMiniStats()
 }
 
 // class TupleConstantOnlyStep
-TupleConstantOnlyStep::TupleConstantOnlyStep(const JobInfo& jobInfo) : TupleConstantStep(jobInfo)
+TupleConstantOnlyStep::TupleConstantOnlyStep(const JobInfo& jobInfo)
+  : TupleConstantStep(jobInfo)
+  , fEmptySet(jobInfo.constantFalse)
 {
   //	fExtendedInfo = "TCOS: ";
 }
@@ -667,7 +671,10 @@ void TupleConstantOnlyStep::run()
 
       fillInConstants();
 
-      fOutputDL->insert(rgDataOut);
+      if (!fEmptySet)
+      {
+        fOutputDL->insert(rgDataOut);
+      }
     }
     catch (...)
     {

dbcon/joblist/tupleconstantstep.h

@@ -132,6 +132,7 @@ class TupleConstantOnlyStep : public TupleConstantStep
   uint32_t nextBand(messageqcpp::ByteStream& bs) override;
 
  protected:
+  bool fEmptySet;
   using TupleConstantStep::fillInConstants;
   void fillInConstants() override;
 };

mysql-test/columnstore/bugfixes/MCOL-4942-constant-select-empty-set.result

@@ -0,0 +1,22 @@
+DROP DATABASE IF EXISTS MCOL4942;
+CREATE DATABASE MCOL4942;
+USE MCOL4942;
+CREATE TABLE t1col (id INT) ENGINE=Columnstore;
+SELECT * FROM
+(
+SELECT ID
+FROM
+(
+SELECT 1 ID
+FROM 
+t1col
+) V
+UNION ALL
+SELECT ID
+FROM
+(
+SELECT NULL ID WHERE 1111=2222
+) V
+) U;
+ID
+DROP DATABASE MCOL4942;

mysql-test/columnstore/bugfixes/MCOL-4942-constant-select-empty-set.test

@@ -0,0 +1,40 @@
+--disable_warnings
+DROP DATABASE IF EXISTS MCOL4942;
+--enable_warnings
+CREATE DATABASE MCOL4942;
+USE MCOL4942;
+CREATE TABLE t1col (id INT) ENGINE=Columnstore;
+
+SELECT * FROM
+
+(
+
+	SELECT ID
+
+	FROM
+
+	(
+
+		SELECT 1 ID
+
+		FROM 
+
+		t1col
+
+	) V
+
+	UNION ALL
+
+	SELECT ID
+
+	FROM
+
+	(
+
+		SELECT NULL ID WHERE 1111=2222
+
+	) V
+
+) U;
+
+DROP DATABASE MCOL4942;

utils/loggingcpp/exceptclasses.h

@@ -283,6 +283,24 @@ class ProtocolError : public std::logic_error
     }                                                                                      \
   } while (0)
 
+#define idblog(x)                                                                       \
+  do                                                                                       \
+  {                                                                                        \
+    {                                                                                      \
+      std::ostringstream os;                                                               \
+                                                                                           \
+      os << __FILE__ << "@" << __LINE__ << ": \'" << x << "\'"; \
+      std::cerr << os.str() << std::endl;                                                  \
+      logging::MessageLog logger((logging::LoggingID()));                                  \
+      logging::Message message;                                                            \
+      logging::Message::Args args;                                                         \
+                                                                                           \
+      args.add(os.str());                                                                  \
+      message.format(args);                                                                \
+      logger.logErrorMessage(message);                                                     \
+    }                                                                                      \
+  } while (0)
+
 #define idbassert_s(x, s)                                                                                \
   do                                                                                                     \
   {                                                                                                      \