WL10034 DEV API Views DDL Support.

Implemented Drop View support and unit tests.

Author: Roberto Garcia

CHANGES

@@ -1,6 +1,7 @@
 7.0.7
 - MySqlX: Fixed configuration handling paths in Linux and MacOS (Oracle Bug #25423724).
 - MySqlX: Fixed Dispose error in Linux and MacOS (Oracle Bug #25423700).
+- MySqlX: Added support for creating, modifying, and dropping Views.
 
 
 7.0.6

Source/MySql.Data/X/Protocol/X/XProtocol.cs

@@ -574,5 +574,13 @@ internal void SendModifyView(string schema, string name, string definer, ViewAlg
       }
       _writer.Write((int)ClientMessages.Types.Type.CrudModifyView, builder);
     }
+
+    internal void SendDropView(string schema, string name, bool ifExists)
+    {
+      var builder = new DropView();
+      builder.Collection = ExprUtil.BuildCollection(schema, name);
+      builder.IfExists = ifExists;
+      _writer.Write((int)ClientMessages.Types.Type.CrudDropView, builder);
+    }
   }
 }

Source/MySql.Data/X/Session/XInternalSession.cs

@@ -347,5 +347,12 @@ public Result ViewAlter(ViewAlterStatement statement)
         statement.columns, statement.queryStatement);
       return new Result(this);
     }
+
+    public Result ViewDrop(ViewDropStatement statement)
+    {
+      protocol.SendDropView(statement.Target.Schema.Name, 
+        statement.name, statement.ifExists);
+      return new Result(this);
+    }
   }
 }

Source/MySql.Data/X/XDevAPI/Common/ViewDropStatement.cs

@@ -27,16 +27,34 @@
 
 namespace MySqlX.XDevAPI.Common
 {
-  public class ViewDropStatement : BaseStatement<Result>
+  public class ViewDropStatement : TargetedBaseStatement<Schema, Result>
   {
-    internal ViewDropStatement(BaseSession session, string name) : base(session)
+    internal string name;
+    internal bool ifExists = false;
+
+    internal ViewDropStatement(Schema schema, string name) : base(schema)
     {
+      this.name = name;
+    }
 
+    /// <summary>
+    /// Supress error if the view to drop doesn't exist.
+    /// </summary>
+    /// <returns></returns>
+    public ViewDropStatement IfExists()
+    {
+      ifExists = true;
+      return this;
     }
 
+    /// <summary>
+    /// Executes the view drop statement
+    /// </summary>
+    /// <returns>Result of execution</returns>
     public override Result Execute()
     {
-      throw new NotImplementedException();
+      if (string.IsNullOrWhiteSpace(name)) throw new ArgumentNullException("Name");
+      return Session.XSession.ViewDrop(this);
     }
   }
 }

Source/MySql.Data/X/XDevAPI/Schema.cs

@@ -192,7 +192,7 @@ public ViewAlterStatement AlterView(string name)
     /// <returns>ViewDrop chaining object</returns>
     public ViewDropStatement DropView(string name)
     {
-      return new ViewDropStatement(Session, name);
+      return new ViewDropStatement(this, name);
     }
 
     #endregion

Tests/MySqlX.Data.Tests/CrudViewsTests.cs

@@ -173,6 +173,21 @@ public void CreateViewNullValidations()
       Assert.Equal("Definer", Assert.ThrowsAny<ArgumentNullException>(() => db.CreateView("myview").DefinedAs(table.Select()).Definer(null).Execute()).ParamName);
     }
 
+    [Fact]
+    public void CreateViewReplace()
+    {
+      CreateBasicViewFromTable();
+      Schema db = GetSession().Schema;
+      Table table = db.GetTable(tableName);
+      db.CreateView("myview", true)
+        .DefinedAs(table.Select("id"))
+        .Execute();
+
+      var result = GetNodeSession().SQL("DESC myview").Execute().FetchAll();
+      Assert.Equal(1, result.Count);
+      Assert.Equal("id", result[0]["field"]);
+    }
+
     #endregion
 
     #region Alter View
@@ -225,5 +240,35 @@ public void AlterViewFromCollection()
     }
 
     #endregion
+
+    #region Drop View
+
+    [Fact]
+    public void DropTableView()
+    {
+      CreateBasicViewFromTable();
+      Assert.True(GetSession().Schema.GetTable("myview").ExistsInDatabase());
+      GetSession().Schema.DropView("myview").Execute();
+      Assert.False(GetSession().Schema.GetTable("myview").ExistsInDatabase());
+    }
+
+    [Fact]
+    public void DropCollectionView()
+    {
+      CreateBasicViewFromCollection();
+      Assert.True(GetSession().Schema.GetTable("myview").ExistsInDatabase());
+      GetSession().Schema.DropView("myview").Execute();
+      Assert.False(GetSession().Schema.GetTable("myview").ExistsInDatabase());
+    }
+
+    [Fact]
+    public void DropViewIfExists()
+    {
+      Assert.False(GetSession().Schema.GetTable("viewNotExists").ExistsInDatabase());
+      Assert.ThrowsAny<MySqlException>(() => GetSession().Schema.DropView("viewNotExists").Execute());
+      GetSession().Schema.DropView("viewNotExists").IfExists().Execute();
+    }
+
+    #endregion
   }
 }