Re-introduction of GeneratePseudoFromClause for specific "empty" FROM…

… clauses.
dotnet · Nov 26, 2019 · 67b36d3 · 67b36d3
1 parent 93d5bfb
commit 67b36d3
Showing 1 changed file with 12 additions and 0 deletions.
diff --git a/src/EFCore.Relational/Query/QuerySqlGenerator.cs b/src/EFCore.Relational/Query/QuerySqlGenerator.cs
@@ -157,6 +157,10 @@ protected override Expression VisitSelect(SelectExpression selectExpression)
 
                 GenerateList(selectExpression.Tables, e => Visit(e), sql => sql.AppendLine());
             }
+            else
+            {
+                GeneratePseudoFromClause();
+            }
 
             if (selectExpression.Predicate != null)
             {
@@ -193,6 +197,14 @@ protected override Expression VisitSelect(SelectExpression selectExpression)
             return selectExpression;
         }
 
+        /// <summary>
+        ///     Generates a pseudo FROM clause. Required by some providers
+        ///     when a query has no actual FROM clause.
+        /// </summary>
+        protected virtual void GeneratePseudoFromClause()
+        {
+        }
+
         protected override Expression VisitProjection(ProjectionExpression projectionExpression)
         {
             Visit(projectionExpression.Expression);