Question

我想创建一个table_2和variable不同的table_1值的CREATE TABLE `table_2` AS SELECT DISTINCT(CAST(variable AS NUMERIC)) FROM `table_1`;，然后将它们从STRING预先转换为NUMERIC。

我的猜测是：

//index.pug

extends layout

block campground 
  - var campgrounds = '#{camps}'
    .row
      each campground in campgrounds
        div.col-md-3.col-sm-6
          div
            img(src=`${campground.image}` class='img-thumbnail')
            a(href=`/campgrounds/${campground._id}`)
              h4.caption.text-center #{campground.name}





//app.js

app.get('/campgrounds', async (req, res) => {
    try {
        const camps = await Camp.find();
        res.render('index', { camps: camps });
    } catch (ex) {
        res.status(500).send('internal error');
    }
});

但这不起作用。有什么建议吗？

Answer 1

DISTINCT不需要括号。您还需要命名输出列。试试这个：

CREATE TABLE `table_2` AS
SELECT DISTINCT CAST(variable AS NUMERIC) AS variable
FROM `table_1`;

Answer 2

尝试一下：

CREATE TABLE `table_2` AS
  SELECT CAST(variable AS NUMERIC)
  FROM `table_1`
  GROUP BY variable;

在BigQuery中结合使用CAST和SELECT吗？

2 个答案: