我在cassandra 数据库中订购数据有问题.这是我的表结构:
CREATE TABLE posts (
id uuid,
created_at timestamp,
comment_enabled boolean,
content text,
enabled boolean,
meta map<text, text>,
post_type tinyint,
summary text,
title text,
updated_at timestamp,
url text,
user_id uuid,
PRIMARY KEY (id, created_at)
) WITH CLUSTERING ORDER BY (created_at DESC)
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当我运行此查询时,我收到以下消息:
查询:
select * from posts order by created_at desc;
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消息:
ORDER BY is only supported when the partition key is restricted by an EQ or an IN.
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或者此查询返回数据而不进行排序:
select * from …Run Code Online (Sandbox Code Playgroud) 我有一个JavaScript函数:
function test(arr, index) {
for (var i = 0; i < arr.length; i++) {
console.log(arr[i].index);
}
}
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我把这个函数称为:
test(myArr, 'name')
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但它回来了undefined.当我直接使用函数时,它会起作用:
for (var i = 0; i < myArr.length; i++) {
console.log(myArr[i].name);
}
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这是我的阵列:
var myArr = [{name: "hamed"}, {name: "hamed1"}]
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我不认为在调用函数时我应该使用单引号但是没有引号它也不起作用.