单选题

You have enabled the Slow Query Log for a short period. When you process the Slow Query Log, you receive the following snip of output: Count: 100 Time=0 .22a (22s) Lock=0.00s (0s) Rows=0.0 (0), root[root] @localhost CREATE TABLE 't1' (id serial,id0 varchar(N) unique key,intcaoll INT (N) ,intco12 INT(N) ,intco13 INT(N) ,intco14 INT(N) ,intco15 INT(N) ,charcol1 VARVHAR(N) ,charcol2 VARCHAR(N) charcol3 VARCHAR (N) ,charcol4 VARVHAR(N) ,charcol5 VARCHAR(N) charcol6 VARCHAR (N) ,charcol7 VARVHAR(N) ,charcol8 VARCHAR(N) charcol9 VARCHAR (N) .charcol 10 VACHAR (N) ) Count: 64000 Time-0.02s (1213s) Lock=0.00s (6s) Rows=1.0 (64000), root [root]@ localhost SELECT intocl1, intco12, intco13, intco14, intco15, intco16,intco17, intco18 ,intcol9, intcol10, charcol1, charcol2, charcol3, charcol4, charcol5, charcol6 ,charcol7, charcol8, charcol9, charcol10 FROM t1 WHERE id = 's' Count: 1 Time=0.02s (0s) Lock=0.00s (0s) Rows=1.0 (1) agent [agent] @localhost SELECT Select_priv, Repl_client_priv, Show_db_priv, Super_priv, Process_priv FROM mysql.user WHERE CONCAT (user, 's', host) = CURRENT_USER ( ) Count: 48000 Time=0.02s (778s) Lock=0.00 (3s) Rows=1.0 (48000), root[root]@localhost SELECT intocl1,intcol2,intcol3, intcol4, intcol5, charcol1, charcol2, charcol3 ,charcol4, charcol5, charcol6, charcol7, charcol8, charcol9, charcol10 FROM t1 WHERE id = 's' You want to tune the query such that it provides the greatest overall time savings. Which query will accomplish this?()

A. CHEATE TABLE 't1' (id serial, id0 varchar (N) unique key, intcol1 INT (N) ,intcol2 INT (N), intcol3 INT(N) ,intcol4 INT(N), intcol5 INT(N), charool1 VARCHAR (N) ,charcol2 VARCHAR (N), charcol3 VARCHAR(N), charcol4 VARCHAR(N), charcol5 VARCHAR (N) ,charcol6 VARCHAR (N), charcol7 VARCHAR(N), charcol8 VARCHAR(N), charcol9 VARCHAR (N) ,charcol10 VARCHAR (N)
B. SELECT intcol1, intcol2, intcol3, intcol4, intcol5, intcol6, intcol7, intcol8, intcol9, Intcol10, intcol11, intcol12, intcol13, intcol14, intcol15, intcol16, intcol17, intcol18, intcol19, charcol10 FROM t1 WHERE id = 's'
C. SELECT Select_priv, Repl_client_priv, Show_db_priv, Super_priv, Process_priv FROM mysql.user WHERE CONCAT (user,'s', host) = CURRENT_USER()
D. SELECT intcol1, intcol2, intcol3, intcol4, intcol5, charcol1, charcol2, charcol3, charcol4, charcol5, charcol6, charcol7, charcol8, charcol9, charcol10 FROM t1 WHERE id = 's'

查看答案
该试题由用户947****95提供 查看答案人数:45669 如遇到问题请 联系客服
正确答案
该试题由用户947****95提供 查看答案人数:45670 如遇到问题请联系客服

相关试题

换一换
热门试题
购买搜题卡 会员须知 | 联系客服
会员须知 | 联系客服
关注公众号,回复验证码
享30次免费查看答案
微信扫码关注 立即领取
恭喜获得奖励,快去免费查看答案吧~
去查看答案
全站题库适用,可用于E考试网网站及系列App

    只用于搜题看答案,不支持试卷、题库练习 ,下载APP还可体验拍照搜题和语音搜索

    支付方式

     

     

     
    首次登录享
    免费查看答案20
    微信扫码登录 账号登录 短信登录
    使用微信扫一扫登录
    登录成功
    首次登录已为您完成账号注册,
    可在【个人中心】修改密码或在登录时选择忘记密码
    账号登录默认密码:手机号后六位