From 2eede4b09ad189c985fb900410c2602c99678b0d Mon Sep 17 00:00:00 2001
From: Jinyang Li <410670140@qq.com>
Date: Thu, 5 Feb 2026 03:05:12 -0500
Subject: [PATCH] fix(mysql): use lenient flag comparison for ENUM types

TiDB (and potentially other MySQL-compatible databases) may return
ENUM columns with additional flags like NOT_NULL or NO_DEFAULT_VALUE.
The previous exact flag comparison caused type mismatches even though
both sides were valid ENUM types.

This change makes ENUM comparison check only that both types have the
ENUM flag set, ignoring other flags that don't affect type compatibility.

Fixes #3750
Refs #1241
---
 sqlx-mysql/src/type_info.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/sqlx-mysql/src/type_info.rs b/sqlx-mysql/src/type_info.rs
index d37997b665..418d6cdd10 100644
--- a/sqlx-mysql/src/type_info.rs
+++ b/sqlx-mysql/src/type_info.rs
@@ -110,6 +110,11 @@ impl PartialEq<MySqlTypeInfo> for MySqlTypeInfo {
             | ColumnType::String
             | ColumnType::VarString
             | ColumnType::Enum => {
+                // For ENUM types, only require both have ENUM flag set (TiDB compatibility)
+                // TiDB may return additional flags like NOT_NULL that don't affect type compatibility
+                if self.flags.contains(ColumnFlags::ENUM) && other.flags.contains(ColumnFlags::ENUM) {
+                    return true;
+                }
                 return self.flags == other.flags;
             }
             _ => {}