MySQL 语法错误：使用 "== 0" 比较操作符

控制台报错是因为在 SQL 语句中使用了'== 0'的比较操作符，而 MySQL 中应使用'= 0'进行比较。

修正后的 SQL 语句如下：

select count(0) from (
    select DISTINCT caseAss.* from (
        SELECT
            a.SCENA_CODE as 'scenaCode',
            a.CASE_CODE as 'caseCode',
            a.ROAD_CODE as 'linkRoads',
            a.CASE_DESCRIBE as 'caseDescribe',
            a.CASE_TYPE as 'caseType',
            ltctn.TYPE_NAME as 'caseTypeName',
            a.TEST_OBJECTIVE as 'testObjective',
            a.TEST_CONDITION as 'testCondition',
            a.CREATE_USER as 'createUser',
            a.UPDATE_USER as 'updateUser',
            a.remark as 'remark',
            a.id as 'id',
            a.create_by as 'createBy',
            a.create_dept as 'createDept',
            a.create_time as 'createTime',
            a.update_by as 'updateBy',
            a.update_time as 'updateTime',
            a.update_ip as 'updateIp',
            a.version as 'version',
            a.del_flag as 'delFlag',
            lsm.SCENA_CODE AS 'name',
            ltctn.PARENT_NAMES as 'caseTypeNames'
        FROM
            lts_test_case_manage a
            left join lts_test_case_type_new ltctn on a.CASE_TYPE = ltctn.id
            left join lts_scena_manage lsm ON a.SCENA_CODE = lsm.id
            LEFT JOIN sys_user t ON FIND_IN_SET(t.id,a.create_by)
            left join sys_dept d on t.dept_id = d.id
        WHERE
            a.del_flag = ?
            and (select count(*) from lts_file_info where LINK_CODE = a.id) = 0
    ) caseAss
    ORDER BY caseAss.caseCode ASC
) tmp_count