order by a asc,b desc, c desc /*排序顺序不一致*/ where g=const order by b,c /*丢失a索引*/ where a=const order by c /*丢失b索引*/ where a=const order by a,d /*d不是索引*/ where a in(…) order by b,c /*对于排序来说,in 相当于是范围查询*/ 慢查询 简介 开启慢查询日志...
ahow clearly they explain themselves in class 多么他们清楚地解释自己在类[translate]
1 row in set (0.00 sec) 可以看到,type变为了ref,Extra中的Using filesort也消失了,结果非常理想。 再来看一个多表查询的例子。 首先定义3个表class和room。 复制代码代码如下: CREATE TABLE IF NOT EXISTS `class` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `card` int(10) unsigned NOT NUL...
order by b,c where a=const and b > const order by b,c 不能使用索引进行排序 order by a asc,b desc, c desc /*排序顺序不一致*/ where g=const order by b,c /*丢失a索引*/ where a=const order by c /*丢失b索引*/ where a=const order by a,d /*d不是索引*/ where a in(…)...
a IN (SELECT t2.b FROM t2 WHERE where_condition); 优化器可能将此重写为 EXISTS相关子查询: 代码语言:javascript 复制 SELECT * FROM t1 WHERE EXISTS (SELECT t2.b FROM t2 WHERE where_condition AND t1.a=t2.b); 2.4.3 开启方式 使用物化子查询前需开启 optimizer_switch 系统变量的 ...
apic1#moquery -c l2IngrPktsAg15min This provides all object instances for this class l2IngrPktsAg15min. Here is an example with a filter to query a specific object. In this example, the filter is to show only an object with attributes dn which includes ...
The following example shows how you can use theExplanationClientclass to enable model interpretability for remote runs. It’s conceptually similar to the local process, except you: Use theExplanationClientin the remote run to upload the interpretability context. ...
听力原文:M: Could you please explain the assignment for Monday, Miss Smith?W: Certainly.Read the next chapter in your textbook and come to class prepared to discuss what you've read.Q: What is the probable relationship between the two speakers?(10)A.Secretary-Pass.B.Client - Lawyer.C....
Voice Class Route-String call-route (dest-route-string) 15.3(3)M 3.10S Dial-Peer Groups (VOIP) E164-Pattern-Maps (Inbound) Destination Server Group requri-passing session target (sip-uri) 15.4(1)T 3.11S Dial-peer Provision Policy SIP-Profiles (Inbound) 15.4(2)T 3...
A. speak loudly B. speak slowly C. make it easy to understand D. make it difficult to understand 相关知识点: 试题来源: 解析 C。“explain clearly”意思是解释清楚,也就是让问题容易理解。A 选项是大声说;B 选项是慢慢说;D 选项是让问题难以理解,都不符合“解释清楚”的意思。反馈...