在实际业务场景中存在关联字段类型不一致的情况，目前的代码在left join关联时发现无法兼容字段类型不一致的情况，需要在sql中拼接cast函数进行转换

如：pg数据库A表id为int、B表id_str为varchar、C表id为int

打印出来的sql为：
SELECT "A".*, "B".*, "C".* FROM "public"."A" AS "A" LEFT JOIN ( SELECT * FROM "public"."B" ) AS "B" ON "B"."id_str" = "A"."id" LEFT JOIN ( SELECT * FROM "public"."C" ) AS "C" ON "C"."id" = "B"."id_str" LIMIT 20000

导致出现类型不匹配的错误

修改代码兼容cast函数后

打印出来的sql为：
SELECT "A".*, "B".*, "C".* FROM "public"."A" AS "A" LEFT JOIN ( SELECT * FROM "public"."B" ) AS "B" ON CAST("B"."id_str" AS integer) = "A"."id" LEFT JOIN ( SELECT * FROM "public"."C" ) AS "C" ON CAST("C"."id" AS varchar) = "B"."id_str" LIMIT 20000

数据响应成功