摘要:
js使用占位符替换字符串是一个ES6中的模版字符串语法。 在``中使用 ${} var a = 5; var b = 10; console.log(`Fifteen is ${a + b} and not ${2 * a + b}.`); Fifteen is 15 and not 20. 阅读全文
摘要:
sql查询某字段的相同值: SELECT * FROM table WHERE col in (SELECT col FROM table GROUP BY col HAVING COUNT (col) >1); 顺带说一下where和having: select * from tablewhere 阅读全文