fix(Bun.SQL): handle binary columns in MySQL correctly (#26011)

## What does this PR do?
Currently binary columns are returned as strings which means they get
corrupted when encoded in UTF8. This PR returns binary columns as
Buffers which is what user's actually expect and is also consistent with
PostgreSQL and SQLite.
### How did you verify your code works?
I added tests to verify the correct behavior. Before there were no tests
for binary columns at all.

This fixes #23991

src/sql/mysql/protocol/DecodeBinaryValue.zig

@@ -1,4 +1,4 @@
-pub fn decodeBinaryValue(globalObject: *jsc.JSGlobalObject, field_type: types.FieldType, column_length: u32, raw: bool, bigint: bool, unsigned: bool, comptime Context: type, reader: NewReader(Context)) !SQLDataCell {
+pub fn decodeBinaryValue(globalObject: *jsc.JSGlobalObject, field_type: types.FieldType, column_length: u32, raw: bool, bigint: bool, unsigned: bool, binary: bool, comptime Context: type, reader: NewReader(Context)) !SQLDataCell {
     debug("decodeBinaryValue: {s}", .{@tagName(field_type)});
     return switch (field_type) {
         .MYSQL_TYPE_TINY => {
@@ -131,6 +131,7 @@ pub fn decodeBinaryValue(globalObject: *jsc.JSGlobalObject, field_type: types.Fi
             else => error.InvalidBinaryValue,
         },
 
+        // When the column contains a binary string we return a Buffer otherwise a string
         .MYSQL_TYPE_ENUM,
         .MYSQL_TYPE_SET,
         .MYSQL_TYPE_GEOMETRY,
@@ -138,7 +139,6 @@ pub fn decodeBinaryValue(globalObject: *jsc.JSGlobalObject, field_type: types.Fi
         .MYSQL_TYPE_STRING,
         .MYSQL_TYPE_VARCHAR,
         .MYSQL_TYPE_VAR_STRING,
-        // We could return Buffer here BUT TEXT, LONGTEXT, MEDIUMTEXT, TINYTEXT, etc. are BLOB and the user expects a string
         .MYSQL_TYPE_TINY_BLOB,
         .MYSQL_TYPE_MEDIUM_BLOB,
         .MYSQL_TYPE_LONG_BLOB,
@@ -151,7 +151,9 @@ pub fn decodeBinaryValue(globalObject: *jsc.JSGlobalObject, field_type: types.Fi
             }
             var string_data = try reader.encodeLenString();
             defer string_data.deinit();
-
+            if (binary) {
+                return SQLDataCell.raw(&string_data);
+            }
             const slice = string_data.slice();
             return SQLDataCell{ .tag = .string, .value = .{ .string = if (slice.len > 0) bun.String.cloneUTF8(slice).value.WTFStringImpl else null }, .free_value = 1 };
         },

src/sql/mysql/protocol/ResultSet.zig

@@ -140,8 +140,12 @@ pub const Row = struct {
                 }
             },
             else => {
-                const slice = value.slice();
-                cell.* = SQLDataCell{ .tag = .string, .value = .{ .string = if (slice.len > 0) bun.String.cloneUTF8(slice).value.WTFStringImpl else null }, .free_value = 1 };
+                if (column.flags.BINARY) {
+                    cell.* = SQLDataCell.raw(value);
+                } else {
+                    const slice = value.slice();
+                    cell.* = SQLDataCell{ .tag = .string, .value = .{ .string = if (slice.len > 0) bun.String.cloneUTF8(slice).value.WTFStringImpl else null }, .free_value = 1 };
+                }
             },
         };
     }
@@ -226,7 +230,7 @@ pub const Row = struct {
             }
 
             const column = this.columns[i];
-            value.* = try decodeBinaryValue(this.globalObject, column.column_type, column.column_length, this.raw, this.bigint, column.flags.UNSIGNED, Context, reader);
+            value.* = try decodeBinaryValue(this.globalObject, column.column_type, column.column_length, this.raw, this.bigint, column.flags.UNSIGNED, column.flags.BINARY, Context, reader);
             value.index = switch (column.name_or_index) {
                 // The indexed columns can be out of order.
                 .index => |idx| idx,

test/js/sql/sql-mysql.test.ts

@@ -480,6 +480,25 @@ if (isDockerEnabled()) {
           expect(b).toEqual({ b: 2 });
         });
 
+        test("Binary", async () => {
+          const random_name = ("t_" + Bun.randomUUIDv7("hex").replaceAll("-", "")).toLowerCase();
+          await sql`CREATE TEMPORARY TABLE ${sql(random_name)} (a binary(1), b varbinary(1), c blob)`;
+          const values = [
+            { a: Buffer.from([1]), b: Buffer.from([2]), c: Buffer.from([3]) },
+          ];
+          await sql`INSERT INTO ${sql(random_name)} ${sql(values)}`;
+          const results = await sql`select * from ${sql(random_name)}`;
+          // return buffers
+          expect(results[0].a).toEqual(Buffer.from([1]));
+          expect(results[0].b).toEqual(Buffer.from([2]));
+          expect(results[0].c).toEqual(Buffer.from([3]));
+          // text protocol should behave the same
+          const results2 = await sql`select * from ${sql(random_name)}`.simple();
+          expect(results2[0].a).toEqual(Buffer.from([1]));
+          expect(results2[0].b).toEqual(Buffer.from([2]));
+          expect(results2[0].c).toEqual(Buffer.from([3]));
+        })
+
         test("bulk insert nested sql()", async () => {
           await using sql = new SQL({ ...getOptions(), max: 1 });
           await sql`create temporary table test_users (name text, age int)`;