记一次sql优化，or查询优化与连接索引失效
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优化一个sql，这个sql并不复杂，但执行了错误的执行计划，原始sql如下
EXPLAIN
SELECT
t1.TRANSACTION_ID,
t1.CLIENT_KEY,
t1.RING_NAME,
t1.CMS_RING_NAME,
t1.NICK_NAME,
T1.RING_TYPE,
t1.TTS_CONTENT,
T1.AUDIO_TYPE,
T1.TTS_GENDER,
T1.MSISDN,
t1.TTS_BG_MUSIC_ID,
T1.FILE_PATH,
T1.CMS_FILE_PATH,
T1.LISTEN_FILE_PATH,
T1.CONTENT_ID,
T1.COPYRIGHT_ID,
T1.REAL_COPYRIGHT_ID,
T1.STATE RING_STATE,
T1.CREATE_TIME RING_CREATE_TIME,
T2.ID,
T2.PID,
T2.TYPE STEP_TYPE,
T2.PROVINCE_CODE,
T2.LAST_TIME,
T2.STATE STEP_STATE,
T2.CREATE_TIME STEP_CREATE_TIME,
T3.CMS_CALLBACK_ID
FROM
AB_RING T1,
ab_ring_step T2,
AB_DEPLOY T3
WHERE
T1.TRANSACTION_ID = T2.TRANSACTION_ID
AND
(T2.PID = T3.STEP_ID OR T2.ID = T3.STEP_ID)
and t1.conteNT_ID='600912988981418430'
ORDER BY
T2.CREATE_TIME DESC
LIMIT 0,
10
优化一个sql，这个sql并不复杂，但执行了错误的执行计划，原始sql如下
EXPLAIN
SELE
