统一用词 (┬＿┬)

(SQL)优化分析与方法.md

@@ -197,16 +197,16 @@ limit 15
 
   我们反过来看 SQL，可以看到其中的子查询是
 ```sql
- SELECT b.num, sbxx.SB_ID, sbxx.BB_DM
- FROM agency_tax.sb_sbxx_bbmx sbxx
- LEFT JOIN (
-  SELECT COUNT(*) num, bbmx.SB_ID sbId
-  FROM agency_tax.sb_sbxx_bbmx bbmx
-  WHERE bbmx.STATE = 'Y'
-  GROUP BY bbmx.SB_ID
- ) b ON b.sbId = sbxx.SB_ID
- WHERE sbxx.STATE = 'Y'
- GROUP BY sbxx.ID
+select b.num, sbxx.sb_id, sbxx.bb_dm
+from agency_tax.sb_sbxx_bbmx sbxx
+left join (
+    select count(*) num, bbmx.sb_id sbid
+    from agency_tax.sb_sbxx_bbmx bbmx
+    where bbmx.state = 'y'
+    group by bbmx.sb_id
+) b on b.sbid = sbxx.sb_id
+where sbxx.state = 'Y'
+group by sbxx.id
 ```
   进一步分析发现，这个子查询竟然又嵌套了一个子查询，更令人费解的是，这个查询竟然是对同一张表，通过对 SQL 分析，这个查询的目的应该是提取符合条件的记录总数，然后对外提供查询。