MySQL: 新增支持 slice 的方式传参，以支持 in 子句。

Author: bunnier

mysql/mysql_db_client.go

@@ -121,12 +121,12 @@ func bindArgs(sqlText string, args ...any) (string, []any, error) {
 				return "", nil, fmt.Errorf("%w:\nlack of parameter\nsql = %s", sqlmer.ErrParseParamFailed, namedParsedResult.Sql)
 			}
 		}
+		namedParsedResult.Sql, resultArgs = extendInParams(namedParsedResult.Sql, resultArgs)
 		return namedParsedResult.Sql, resultArgs, nil
 	}
 
 	// slice 语句中使用的顺序未必是递增的，切可能重复引用同一个索引，所以这里也需要整理顺序。
 	for _, paramName := range namedParsedResult.Names {
-
 		if paramName[0] != 'p' { // 要求数字参数的格式为 @p1....@pN
 			return "", nil, fmt.Errorf("%w: parsing parameter failed\nsql = %s", sqlmer.ErrParseParamFailed, namedParsedResult.Sql)
 		}
@@ -149,6 +149,7 @@ func bindArgs(sqlText string, args ...any) (string, []any, error) {
 		resultArgs = append(resultArgs, args[index])
 	}
 
+	namedParsedResult.Sql, resultArgs = extendInParams(namedParsedResult.Sql, resultArgs)
 	return namedParsedResult.Sql, resultArgs, nil
 }
 
@@ -245,6 +246,67 @@ func parseMySqlNamedSql(sqlText string) *mysqlNamedParsedResult {
 	return parsedResult
 }
 
+// extendInParams 用于处理 SQL IN 子句的参数展开
+// 将切片类型的参数展开为多个问号占位符
+func extendInParams(sqlText string, params []any) (string, []any) {
+	var newParams []any = make([]any, 0, len(params))
+	var newSqlBuilder strings.Builder
+
+	paramIndex := 0
+	inString := false
+	for _, r := range sqlText {
+		if r == '\'' {
+			inString = !inString
+			newSqlBuilder.WriteRune(r)
+			continue
+		}
+
+		if inString {
+			newSqlBuilder.WriteRune(r)
+			continue
+		}
+
+		if r != '?' {
+			newSqlBuilder.WriteRune(r)
+			continue
+		}
+
+		if paramIndex >= len(params) { // 后面没参数了，无需判断了。
+			newSqlBuilder.WriteRune(r)
+			continue
+		}
+
+		param := params[paramIndex]
+		paramValue := reflect.ValueOf(param)
+		paramIndex++
+
+		// 处理切片类型。
+		// 排除 []byte，因为虽然 []byte 也是切片类型，但是它是二进制数据，不应该被展开。
+		if paramValue.Kind() == reflect.Slice && paramValue.Type() != reflect.TypeOf([]byte{}) {
+			paramLen := paramValue.Len()
+			if paramLen == 0 {
+				// 空切片替换为 SQL 不可能条件。
+				newSqlBuilder.WriteString("NULL")
+				continue
+			}
+
+			// 生成占位符。
+			placeholders := strings.Repeat(",?", paramLen)
+			newSqlBuilder.WriteString(placeholders[1:])
+
+			// 展开参数。
+			for i := 0; i < paramLen; i++ {
+				newParams = append(newParams, paramValue.Index(i).Interface())
+			}
+		} else {
+			newSqlBuilder.WriteRune('?')
+			newParams = append(newParams, param)
+		}
+	}
+
+	return newSqlBuilder.String(), newParams
+}
+
 // getScanTypeFn 根据驱动配置返回一个可以正确获取 Scan 类型的函数。
 func getScanTypeFn(cfg *mysqlDriver.Config) sqlen.GetScanTypeFunc {
 	var scanTypeRawBytes = reflect.TypeOf(sql.RawBytes{})

mysql/mysql_db_client_test.go

@@ -52,7 +52,7 @@ func Test_internalDbClient_Scalar(t *testing.T) {
 		wantErr bool
 	}{
 		{
-			"mysql",
+			"mysql1",
 			mysqlClient,
 			args{
 				"SELECT Id FROM go_TypeTest WHERE id=@p1",
@@ -61,6 +61,26 @@ func Test_internalDbClient_Scalar(t *testing.T) {
 			int64(1),
 			false,
 		},
+		{
+			"mysql2",
+			mysqlClient,
+			args{
+				"SELECT Id FROM go_TypeTest WHERE id in (@p1)",
+				[]any{[]int{1}},
+			},
+			int64(1),
+			false,
+		},
+		{
+			"mysql3",
+			mysqlClient,
+			args{
+				"SELECT COUNT(1) FROM go_TypeTest WHERE id in (@p1)",
+				[]any{[]int{1, 2, 3}},
+			},
+			int64(3),
+			false,
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {

mysql/mysql_test.go

@@ -43,6 +43,64 @@ func Test_parseMySqlNamedSql(t *testing.T) {
 	}
 }
 
+func TestExtendInParams(t *testing.T) {
+	tests := []struct {
+		name      string
+		sql       string
+		params    []any
+		expSQL    string
+		expParams []any
+	}{
+		{
+			"single",
+			"select 1 from t where id = ?",
+			[]any{1},
+			"select 1 from t where id = ?",
+			[]any{1},
+		},
+		{
+			"slice1",
+			"select 1 from t where id in (?)",
+			[]any{[]int{1, 2, 3}},
+			"select 1 from t where id in (?,?,?)",
+			[]any{1, 2, 3},
+		},
+		{
+			"singleWithSlice",
+			"select 1 from t where id!=? AND id in (?)",
+			[]any{5, []int{1, 2, 3}},
+			"select 1 from t where id!=? AND id in (?,?,?)",
+			[]any{5, 1, 2, 3},
+		},
+		{
+			"empty",
+			"select 1 from t where id in (?)",
+			[]any{[]int{}},
+			"select 1 from t where id in (NULL)",
+			[]any{},
+		},
+		{
+			"regular",
+			"select 1 from t where name = ? and age = ?",
+			[]any{"Alice", 30},
+			"select 1 from t where name = ? and age = ?",
+			[]any{"Alice", 30},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gotSQL, gotParams := extendInParams(tt.sql, tt.params)
+			if gotSQL != tt.expSQL {
+				t.Errorf("Expected SQL: %s, got: %s", tt.expSQL, gotSQL)
+			}
+			if !reflect.DeepEqual(gotParams, tt.expParams) {
+				t.Errorf("Expected Params: %v, got: %v", tt.expParams, gotParams)
+			}
+		})
+	}
+}
+
 func Test_bindMySqlArgs(t *testing.T) {
 	testCases := []struct {
 		name      string
@@ -157,6 +215,31 @@ func Test_bindMySqlArgs(t *testing.T) {
 			[]any{3, 3},
 			nil,
 		},
+		{
+			"inwhere1",
+			"SELECT * FROM go_TypeTest WHERE id IN (@ids)",
+			[]any{
+				map[string]any{
+					"ids": []int{1, 2, 3},
+				},
+			},
+			"SELECT * FROM go_TypeTest WHERE id IN (?,?,?)",
+			[]any{1, 2, 3},
+			nil,
+		},
+		{
+			"inwhere2",
+			"SELECT * FROM go_TypeTest WHERE id!=@noid AND id IN (@ids)",
+			[]any{
+				map[string]any{
+					"noid": 4,
+					"ids":  []int{1, 2, 3},
+				},
+			},
+			"SELECT * FROM go_TypeTest WHERE id!=? AND id IN (?,?,?)",
+			[]any{4, 1, 2, 3},
+			nil,
+		},
 	}
 
 	for _, tt := range testCases {