sql - InfluxDB 占位符“空绑定参数”

Question

我正在努力使用占位符格式化 InfluxDB 查询。

在这里，我使用多个占位符进行查询。这些值在占位符对象中定义，如下所示，

let query = `SELECT grid_ref_x, grid_ref_y, label FROM position
WHERE "label" = $<label> and time >= $<from> - $<interval>`;

const placeholders = {label: 'person', from: 'now()', interval: '5m'};
const resp = await influx.query(query, { placeholders });

一旦发送，一个error 400 - error parsing query: empty bound parameter

在错误中，我可以看到 GET 请求，其中似乎 Influx 库已正确格式化“参数”下的占位符。

/query?p=root&u=root&db=heatmap&epoch=&q=SELECT grid_ref_x, grid_ref_y, label FROM position WHERE label = $<label> and time >= $<from> - $<interval>&rp=&params={"from":"now()","interval":"5h","label":"person"}

如何正确格式化我的查询？

Answer 1

你试过改变

let query = `SELECT grid_ref_x, grid_ref_y, label FROM position
WHERE "label" = $<label> and time >= $<from> - $<interval>`;

至

let query = `SELECT grid_ref_x, grid_ref_y, label FROM position
WHERE "label" = $label and time >= $from - $interval`;

不同之处在于您使用$variable_name而不是$<variable_name>引用占位符或绑定参数。假设您使用的是 node_influx，您可以删除标签上的双引号，它仍然可以工作。

我用这个 PR 作为参考https://github.com/node-influx/node-influx/issues/587