node.js-從mysql查詢中調用javascript變量

Question

我正在嘗試從mySQL查詢中調用javascript變量。 這些行在node.js環境中使用語法[node（filename）]執行。 我了解我可以分兩步執行此查詢，方法是先查詢min_value的值，然后查詢max_value。

可以在一個mySQL查詢中執行請求嗎？

最好是，我希望保留香草js和mySQL的代碼結構，而無需添加特定於node.js的命令，也無需加載額外的程序包。

JavaScript變量：

let min_value = 100;
let max_value = 300;

這有效：

sql = `
 SELECT
   acronym,
   salaries
 FROM 
   employees
 WHERE
   salaries BETWEEN 100 and 300
ORDER BY acronym;
`;

這不起作用：

sql = `
 SELECT
   acronym,
   salaries
 FROM 
   employees
 WHERE
   salaries BETWEEN ($min_value) and ($max_value)
ORDER BY acronym;
`;

Answer 1

嘗試使用${variable}占位符語法使用Template Literals ：

 let min_value = 100; let max_value = 300; let sql1 = ` SELECT acronym, salaries FROM employees WHERE salaries BETWEEN (${min_value}) and (${max_value}) ORDER BY acronym; `; let sql2 = ` SELECT acronym, salaries FROM employees WHERE salaries BETWEEN ${min_value} and ${max_value} ORDER BY acronym; `; console.log(sql1); console.log(sql2);