Fixed statement generation involving negative subqueries

Previously, we generated negative subqueries by integrating them into
the main statement normally, and then making the connecting join be a
LEFT JOIN instead of an INNER JOIN, and by adding a condition that the
join column be NULL. The problem with this is that if the top table of
the subquery joins against any other table (which join throughs always
do), then no rows will be returned. This was solved by putting the
subquery into a CTE and then LEFT JOINing as before with the CTE.

1 files changed, 13 insertions, 3 deletions

@@ -184,13 +184,15 @@ namespace verbly {
         std::map<std::string, std::string> tables,
         std::string topTable,
         condition where,
-        std::list<join> joins) :
+        std::list<join> joins,
+        bool recursive) :
           identifier_(std::move(identifier)),
           field_(f),
           tables_(std::move(tables)),
           topTable_(std::move(topTable)),
           topCondition_(std::move(where)),
-          joins_(std::move(joins))
+          joins_(std::move(joins)),
+          recursive_(recursive)
       {
       }
       
@@ -224,6 +226,11 @@ namespace verbly {
         return joins_;
       }
       
+      bool isRecursive() const
+      {
+        return recursive_;
+      }
+      
     private:
       std::string identifier_;
       field field_;
@@ -231,6 +238,7 @@ namespace verbly {
       std::string topTable_;
       condition topCondition_;
       std::list<join> joins_;
+      bool recursive_;
       
     };
     
@@ -254,7 +262,9 @@ namespace verbly {
     
     std::string instantiateTable(std::string name);
     
-    condition integrate(statement subStmt);
+    std::string instantiateWith(std::string name);
+    
+    condition integrate(statement subStmt, bool cte = false);
     
     int nextTableId_;
     int nextWithId_;