Question

sql语句，列名为数字怎么办

select sum(列名) from table1，如果列明是数字怎么办？
直接写数字算出是数字的和，加引号报错

Answer 1

select sum("列名") from table1

列名加上半角英文的双引号即可

Answer 2

把表名加上试试select sum( table1.列名) from table1

Answer 3

select sum(列名) as 新列名 from table1