启动
下载安装后,从目录来看,只支持linux的命令行。
直接进入到jaql目录,运行jaqlShell即可,为了方便,export到PATH变量中。
$ jaqlShell Initializing Jaql. Starting DataNode 0 with dfs.data.dir: \tmp\jaql\dfs\dfs\data\data1,\tmp\jaql\df s\dfs\data\data2 Waiting for the Mini HDFS Cluster to start... Generating rack names for tasktrackers Generating host names for tasktrackers jaql>
数组操作
定义数组:
jaql> array = [1,2,3,4]; jaql> array2=range(0,100);
数组其它操作
jaql> array[0]; 1 jaql> array2[0:10]; [ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ]替换元素
jaql> array=replaceElement(array,0,10); jaql> array; [ 10, 2, 3, 4 ]
JSON操作
定义JSON
jaql> persons=[{name:‘Mary‘,age:40,children:[‘Katie‘,‘Rose‘]},{name:‘Mark‘,age:20}]; jaql> persons; [ { "name": "Mary", "age": 40, "children": [ "Katie", "Rose" ] }, { "name": "Mark", "age": 20 } ]
获取部分行数据
jaql> persons[0]; { "name": "Mary", "age": 40, "children": [ "Katie", "Rose" ] } jaql> persons[0].name; "Mary" jaql> persons[0].children[0]; "Katie"
获取部分列数据
jaql> persons[*].name; [ "Mary", "Mark" ]
jaql> persons[*].children; [ [ "Katie", "Rose" ], null ]