即查看sql的执行效率,帮助我们分析select语句,让我们知道查询效率低下的原因,从而改进我们的查询。用法就是sql语句前加explain。 我这有90万条数据的表: 我可以整一条sql让他故意慢下来。 找个对照表 参考一下,这个根据你们实际的情况。 extra列返回的描述的意义 distinct:一旦mysql找到了与行相联合匹配的行,就不...
2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]/0:0:0:0:0:0:0:0:2181:Environment@100] - Server environment:java.home=/usr/lib/jvm/java-7-openjdk-amd64/jre 2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]...
[myid=3]/0:0:0:0:0:0:0:0:2181:Environment@100] - Server environment:java.home=/usr/lib/jvm/java-7-openjdk-amd64/jre 2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]/0:0:0:0:0:0:0:0:2181:Environment@100] - Server environment:java.class.path=/...
space. these forces can be categorized as either concurrent forces, which have their lines of action intersect at a single point, or non-concurrent forces, where the lines of action do not meet at a common point. by analyzing the components of these forces and their respective directions, ...
2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]/0:0:0:0:0:0:0:0:2181:Environment@100] - Server environment:java.home=/usr/lib/jvm/java-7-openjdk-amd64/jre 2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]/0:...
2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]/0:0:0:0:0:0:0:0:2181:Environment@100] - Server environment:java.home=/usr/lib/jvm/java-7-openjdk-amd64/jre 2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]/0:0:0:0:0:0...
[myid=3]/0:0:0:0:0:0:0:0:2181:Environment@100] - Server environment:java.home=/usr/lib/jvm/java-7-openjdk-amd64/jre 2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]/0:0:0:0:0:0:0:0:2181:Environment@100] - Server environment:...
2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]/0:0:0:0:0:0:0:0:2181:Environment@100] - Server environment:java.home=/usr/lib/jvm/java-7-openjdk-amd64/jre 2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]/0:0...
2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]/0:0:0:0:0:0:0:0:2181:Environment@100] - Server environment:java.home=/usr/lib/jvm/java-7-openjdk-amd64/jre 2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]/0:0:0:0:...
[myid=3]/0:0:0:0:0:0:0:0:2181:Environment@100] - Server environment:java.home=/usr/lib/jvm/java-7-openjdk-amd64/jre 2017-01-22 23:47:29,661 [myid:3] - INFO [QuorumPeer[myid=3]/0:0:0:0:0:0:0:0:2181:Environment@100] - Server environment:java...