Support for isc_info_sql_explain_plan (DNET-864).

Author: cincuranet

Provider/src/FirebirdSql.Data.FirebirdClient.Tests/FbCommandTests.cs

@@ -738,6 +738,35 @@ public void CommandCancellationTest()
 			}
 		}
 
+		[Test]
+		public void CommandPlanTest()
+		{
+			using (var cmd = Connection.CreateCommand())
+			{
+				cmd.CommandText = "select * from test";
+				cmd.Prepare();
+				var plan = default(string);
+				Assert.DoesNotThrow(() => { plan = cmd.CommandPlan; });
+				Assert.IsNotEmpty(plan);
+			}
+		}
+
+		[Test]
+		public void CommandExplainedPlanTest()
+		{
+			if (!EnsureVersion(new Version(3, 0, 0, 0)))
+				return;
+
+			using (var cmd = Connection.CreateCommand())
+			{
+				cmd.CommandText = "select * from test";
+				cmd.Prepare();
+				var plan = default(string);
+				Assert.DoesNotThrow(() => { plan = cmd.CommandExplainedPlan; });
+				Assert.IsNotEmpty(plan);
+			}
+		}
+
 		[Test]
 		public void NoCommandPlanTest()
 		{
@@ -751,6 +780,22 @@ public void NoCommandPlanTest()
 			}
 		}
 
+		[Test]
+		public void NoCommandExplainedPlanTest()
+		{
+			if (!EnsureVersion(new Version(3, 0, 0, 0)))
+				return;
+
+			using (var cmd = Connection.CreateCommand())
+			{
+				cmd.CommandText = "recreate table NoCommandPlanTest (id int)";
+				cmd.Prepare();
+				var plan = default(string);
+				Assert.DoesNotThrow(() => { plan = cmd.CommandExplainedPlan; });
+				Assert.IsEmpty(plan);
+			}
+		}
+
 		[Test]
 		public void ReadsTimeWithProperPrecision()
 		{

Provider/src/FirebirdSql.Data.FirebirdClient/Common/IscCodes.cs

@@ -606,6 +606,8 @@ internal static class IscCodes
 		public const int isc_info_sql_records = 23;
 		public const int isc_info_sql_batch_fetch = 24;
 		public const int isc_info_sql_relation_alias = 25;
+		public const int isc_info_sql_explain_plan = 26;
+		public const int isc_info_sql_stmt_flags = 27;
 
 		#endregion
 

Provider/src/FirebirdSql.Data.FirebirdClient/Common/StatementBase.cs

@@ -26,19 +26,21 @@ internal abstract class StatementBase : IDisposable
 	{
 		#region Protected Static Fields
 
-		// Plan	information	items
 		protected static readonly byte[] DescribePlanInfoItems = new byte[]
 		{
-			IscCodes.isc_info_sql_get_plan
+			IscCodes.isc_info_sql_get_plan,
+		};
+
+		protected static readonly byte[] DescribeExplaindPlanInfoItems = new byte[]
+		{
+			IscCodes.isc_info_sql_explain_plan,
 		};
 
-		// Records affected	items
 		protected static readonly byte[] RowsAffectedInfoItems = new byte[]
 		{
-			IscCodes.isc_info_sql_records
+			IscCodes.isc_info_sql_records,
 		};
 
-		// Describe	information	items
 		protected static readonly byte[] DescribeInfoAndBindInfoItems = new byte[]
 		{
 			IscCodes.isc_info_sql_select,
@@ -65,12 +67,12 @@ internal abstract class StatementBase : IDisposable
 			IscCodes.isc_info_sql_relation,
 			// IscCodes.isc_info_sql_owner,
 			IscCodes.isc_info_sql_alias,
-			IscCodes.isc_info_sql_describe_end
+			IscCodes.isc_info_sql_describe_end,
 		};
 
 		protected static readonly byte[] StatementTypeInfoItems = new byte[]
 		{
-			IscCodes.isc_info_sql_stmt_type
+			IscCodes.isc_info_sql_stmt_type,
 		};
 
 		#endregion
@@ -107,36 +109,12 @@ public virtual void Dispose()
 
 		public string GetExecutionPlan()
 		{
-			var count = 0;
-			var bufferSize = IscCodes.DEFAULT_MAX_BUFFER_SIZE;
-			var buffer = GetSqlInfo(DescribePlanInfoItems, bufferSize);
-
-			if (buffer[0] == IscCodes.isc_info_end)
-			{
-				return string.Empty;
-			}
-
-			while (buffer[0] == IscCodes.isc_info_truncated && count < 4)
-			{
-				bufferSize *= 2;
-				buffer = GetSqlInfo(DescribePlanInfoItems, bufferSize);
-				count++;
-			}
-			if (count > 3)
-			{
-				return null;
-			}
+			return GetPlanInfo(DescribePlanInfoItems);
+		}
 
-			int len = buffer[1];
-			len += buffer[2] << 8;
-			if (len > 0)
-			{
-				return Database.Charset.GetString(buffer, 4, --len);
-			}
-			else
-			{
-				return string.Empty;
-			}
+		public string GetExecutionExplainedPlan()
+		{
+			return GetPlanInfo(DescribeExplaindPlanInfoItems);
 		}
 
 		public virtual void Close()
@@ -328,6 +306,40 @@ protected void ClearArrayHandles()
 			}
 		}
 
+		protected string GetPlanInfo(byte[] planInfoItems)
+		{
+			var count = 0;
+			var bufferSize = IscCodes.DEFAULT_MAX_BUFFER_SIZE;
+			var buffer = GetSqlInfo(planInfoItems, bufferSize);
+
+			if (buffer[0] == IscCodes.isc_info_end)
+			{
+				return string.Empty;
+			}
+
+			while (buffer[0] == IscCodes.isc_info_truncated && count < 4)
+			{
+				bufferSize *= 2;
+				buffer = GetSqlInfo(planInfoItems, bufferSize);
+				count++;
+			}
+			if (count > 3)
+			{
+				return null;
+			}
+
+			int len = buffer[1];
+			len += buffer[2] << 8;
+			if (len > 0)
+			{
+				return Database.Charset.GetString(buffer, 4, --len);
+			}
+			else
+			{
+				return string.Empty;
+			}
+		}
+
 		#endregion
 	}
 }

Provider/src/FirebirdSql.Data.FirebirdClient/FirebirdClient/FbCommand.cs

@@ -110,6 +110,19 @@ public string CommandPlan
 			}
 		}
 
+		[Browsable(false)]
+		public string CommandExplainedPlan
+		{
+			get
+			{
+				if (_statement != null)
+				{
+					return _statement.GetExecutionExplainedPlan();
+				}
+				return null;
+			}
+		}
+
 		[Category("Behavior")]
 		[DefaultValue(null)]
 		public new FbConnection Connection