fix: replace mariadb's utf8mb4_uca1400_ai_ci with utf8mb4_0900_ai_ci (#…

…312)

.github/workflows/replication-test.yml

@@ -10,7 +10,7 @@ jobs:
     strategy:
       matrix:
         # source: ['mysql', 'postgres', 'dolt', 'mariadb']
-        source: ['mysql', 'postgres']
+        source: ['mysql', 'postgres', 'mariadb']
     steps:
       - uses: actions/checkout@v4
 
@@ -37,9 +37,7 @@ jobs:
               mariadb:latest \
               --gtid-strict-mode=1 \
               --log-bin=mybinlog \
-              --binlog-format=ROW \
-              --character-set-server=utf8mb4 \
-              --collation-server=utf8mb4_general_ci
+              --binlog-format=ROW
 
           elif [ "${{ matrix.source }}" = "dolt" ]; then
             # Create Dolt config

backend/request_modifier.go

@@ -1,11 +1,20 @@
 package backend
 
+import "strings"
+
 // RequestModifier is a function type that transforms a query string
 type RequestModifier func(string, *[]ResultModifier) string
 
 // default request modifier list
 var defaultRequestModifiers = []RequestModifier{}
 
+// Newer MariaDB versions use utf8mb4_uca1400_ai_ci as the default collation,
+// which is not supported by go-mysql-server.
+// This function replaces the collation with the MySQL default utf8mb4_0900_ai_ci.
+func replaceMariaDBCollation(query string, _ *[]ResultModifier) string {
+	return strings.ReplaceAll(query, " utf8mb4_uca1400_ai_ci", " utf8mb4_0900_ai_ci")
+}
+
 // applyRequestModifiers applies request modifiers to a query
 func applyRequestModifiers(query string, requestModifiers []RequestModifier) (string, []ResultModifier) {
 	resultModifiers := make([]ResultModifier, 0)