Throw exception when stored procedure doesn't exist.

Author: bgrainger

src/MySqlConnector/Core/CachedProcedure.cs

@@ -15,26 +15,26 @@ internal sealed class CachedProcedure
 		public static async Task<CachedProcedure> FillAsync(IOBehavior ioBehavior, MySqlConnection connection, string schema, string component, CancellationToken cancellationToken)
 		{
 			var parameters = new List<CachedParameter>();
+			int routineCount;
 			using (var cmd = connection.CreateCommand())
 			{
 				cmd.Transaction = connection.CurrentTransaction;
-				cmd.CommandText = @"SELECT ORDINAL_POSITION, PARAMETER_MODE, PARAMETER_NAME, DATA_TYPE, DTD_IDENTIFIER
+				cmd.CommandText = @"SELECT COUNT(*)
+					FROM information_schema.routines
+					WHERE ROUTINE_SCHEMA = @schema AND ROUTINE_NAME = @component;
+					SELECT ORDINAL_POSITION, PARAMETER_MODE, PARAMETER_NAME, DATA_TYPE, DTD_IDENTIFIER
 					FROM information_schema.parameters
 					WHERE SPECIFIC_SCHEMA = @schema AND SPECIFIC_NAME = @component
 					ORDER BY ORDINAL_POSITION";
-				cmd.Parameters.Add(new MySqlParameter
-				{
-					ParameterName = "@schema",
-					Value = schema
-				});
-				cmd.Parameters.Add(new MySqlParameter
-				{
-					ParameterName = "@component",
-					Value = component
-				});
+				cmd.Parameters.AddWithValue("@schema", schema);
+				cmd.Parameters.AddWithValue("@component", component);
 
 				using (var reader = (MySqlDataReader) await cmd.ExecuteReaderAsync(CommandBehavior.Default, ioBehavior, cancellationToken).ConfigureAwait(false))
 				{
+					await reader.ReadAsync(cancellationToken).ConfigureAwait(false);
+					routineCount = reader.GetInt32(0);
+					await reader.NextResultAsync(cancellationToken).ConfigureAwait(false);
+
 					while (await reader.ReadAsync(cancellationToken).ConfigureAwait(false))
 					{
 						parameters.Add(new CachedParameter(
@@ -48,7 +48,7 @@ FROM information_schema.parameters
 				}
 			}
 
-			return parameters.Count == 0 ? null : new CachedProcedure(schema, component, parameters.AsReadOnly());
+			return routineCount == 0 ? null : new CachedProcedure(schema, component, parameters.AsReadOnly());
 		}
 
 		public ReadOnlyCollection<CachedParameter> Parameters { get; }

src/MySqlConnector/MySql.Data.MySqlClient/MySqlCommandBuilder.cs

@@ -33,14 +33,17 @@ private static async Task DeriveParametersAsync(IOBehavior ioBehavior, MySqlComm
 				throw new NotSupportedException("MySQL Server {0} doesn't support INFORMATION_SCHEMA".FormatInvariant(command.Connection.Session.ServerVersion.OriginalString));
 
 			var cachedProcedure = await command.Connection.GetCachedProcedure(ioBehavior, command.CommandText, cancellationToken).ConfigureAwait(false);
+			if (cachedProcedure == null)
+			{
+				var name = NormalizedSchema.MustNormalize(command.CommandText, command.Connection.Database);
+				throw new MySqlException("Procedure or function '{0}' cannot be found in database '{1}'.".FormatInvariant(name.Component, name.Schema));
+			}
+
 			command.Parameters.Clear();
-			if (cachedProcedure != null)
+			foreach (var cachedParameter in cachedProcedure.Parameters)
 			{
-				foreach (var cachedParameter in cachedProcedure.Parameters)
-				{
-					var parameter = command.Parameters.Add("@" + cachedParameter.Name, cachedParameter.MySqlDbType);
-					parameter.Direction = cachedParameter.Direction;
-				}
+				var parameter = command.Parameters.Add("@" + cachedParameter.Name, cachedParameter.MySqlDbType);
+				parameter.Direction = cachedParameter.Direction;
 			}
 		}
 

tests/SideBySide/StoredProcedureTests.cs

@@ -500,6 +500,16 @@ public void DeriveParametersRemovesExisting()
 			}
 		}
 
+		[Fact]
+		public void DeriveParametersDoesNotExist()
+		{
+			using (var cmd = new MySqlCommand("xx_does_not_exist", m_database.Connection))
+			{
+				cmd.CommandType = CommandType.StoredProcedure;
+				Assert.Throws<MySqlException>(() => MySqlCommandBuilder.DeriveParameters(cmd));
+			}
+		}
+
 		[SkippableFact(ServerFeatures.Json, Baseline = "https://bugs.mysql.com/bug.php?id=89335")]
 		public void DeriveParametersSetJson()
 		{