Parse BIT columns sent as text. Fixes #708

Author: bgrainger

src/MySqlConnector/Core/BinaryRow.cs

@@ -87,11 +87,7 @@ protected override object GetValueCore(ReadOnlySpan<byte> data, ColumnDefinition
 				return isUnsigned ? (object) MemoryMarshal.Read<ulong>(data) : MemoryMarshal.Read<long>(data);
 
 			case ColumnType.Bit:
-				// BIT column is transmitted as MSB byte array
-				ulong bitValue = 0;
-				for (int i = 0; i < data.Length; i++)
-					bitValue = bitValue * 256 + data[i];
-				return bitValue;
+				return ReadBit(data, columnDefinition.ColumnFlags);
 
 			case ColumnType.String:
 				if (Connection.GuidFormat == MySqlGuidFormat.Char36 && columnDefinition.ColumnLength / ProtocolUtility.GetBytesPerCharacter(columnDefinition.CharacterSet) == 36)

src/MySqlConnector/Core/Row.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Buffers.Text;
 using System.IO;
 using System.Runtime.InteropServices;
 using MySql.Data.MySqlClient;
@@ -436,6 +437,26 @@ protected static Guid CreateGuidFromBytes(MySqlGuidFormat guidFormat, ReadOnlySp
 #endif
 		}
 
+		protected static object ReadBit(ReadOnlySpan<byte> data, ColumnFlags columnFlags)
+		{
+			if ((columnFlags & ColumnFlags.Binary) == 0)
+			{
+				// when the Binary flag IS NOT set, the BIT column is transmitted as MSB byte array
+				ulong bitValue = 0;
+				for (int i = 0; i < data.Length; i++)
+					bitValue = bitValue * 256 + data[i];
+				return bitValue;
+			}
+			else
+			{
+				// when the Binary flag IS set, the BIT column is transmitted as text
+				return ParseUInt64(data);
+			}
+		}
+
+		protected static ulong ParseUInt64(ReadOnlySpan<byte> data) =>
+			!Utf8Parser.TryParse(data, out ulong value, out var bytesConsumed) || bytesConsumed != data.Length ? throw new FormatException() : value;
+
 		private void CheckBinaryColumn(int ordinal)
 		{
 			if (m_dataOffsets[ordinal] == -1)

src/MySqlConnector/Core/TextRow.cs

@@ -50,11 +50,7 @@ protected override object GetValueCore(ReadOnlySpan<byte> data, ColumnDefinition
 				return isUnsigned ? (object) ParseUInt64(data) : ParseInt64(data);
 
 			case ColumnType.Bit:
-				// BIT column is transmitted as MSB byte array
-				ulong bitValue = 0;
-				for (int i = 0; i < data.Length; i++)
-					bitValue = bitValue * 256 + data[i];
-				return bitValue;
+				return ReadBit(data, columnDefinition.ColumnFlags);
 
 			case ColumnType.String:
 				if (Connection.GuidFormat == MySqlGuidFormat.Char36 && columnDefinition.ColumnLength / ProtocolUtility.GetBytesPerCharacter(columnDefinition.CharacterSet) == 36)
@@ -129,9 +125,6 @@ private static uint ParseUInt32(ReadOnlySpan<byte> data) =>
 		private static long ParseInt64(ReadOnlySpan<byte> data) =>
 			!Utf8Parser.TryParse(data, out long value, out var bytesConsumed) || bytesConsumed != data.Length ? throw new FormatException() : value;
 
-		private static ulong ParseUInt64(ReadOnlySpan<byte> data) =>
-			!Utf8Parser.TryParse(data, out ulong value, out var bytesConsumed) || bytesConsumed != data.Length ? throw new FormatException() : value;
-
 		private object ParseDateTime(ReadOnlySpan<byte> value)
 		{
 			Exception? exception = null;

tests/SideBySide/DataTypes.cs

@@ -1391,6 +1391,24 @@ public void QueryJson(string column, string[] expected)
 			DoQuery("json_core", column, dataTypeName, expected, reader => reader.GetString(0), omitWhereTest: true);
 		}
 
+		[SkippableTheory(Baseline = "https://bugs.mysql.com/bug.php?id=97067")]
+		[InlineData(false, "MIN", 0)]
+		[InlineData(false, "MAX", uint.MaxValue)]
+		[InlineData(true, "MIN", 0)]
+		[InlineData(true, "MAX", uint.MaxValue)]
+		public void QueryAggregateBit(bool shouldPrepare, string aggregation, ulong expected)
+		{
+			var csb = AppConfig.CreateConnectionStringBuilder();
+			csb.IgnorePrepare = !shouldPrepare;
+			using var connection = new MySqlConnection(csb.ConnectionString);
+			connection.Open();
+			using var command = new MySqlCommand($@"SELECT {aggregation}(Bit32) FROM datatypes_bits;", connection);
+			if (shouldPrepare)
+				command.Prepare();
+			var result = command.ExecuteScalar();
+			Assert.Equal(expected, result);
+		}
+
 		private static byte[] GetBytes(DbDataReader reader)
 		{
 			var size = reader.GetBytes(0, 0, null, 0, 0);