mysql - 我在 R 中编写了一个查询(SQL)来从数据库中获取一些数据。我想传递由 R 中的子例程指定的日期，而不是对其进行硬编码

Question

DATA=dbGetQuery(conn, "SELECT 
                  A, 
                  B as 'Ba',
                  C  as 'Ca',  
                  D as 'Da',
                  date as 'Date'
                  from database where date>='2000-01-01' and date<='2001-01-01' ")

我想用“date1 和 date2”替换“2000-01-01”和“2001-01-01”，两者都在函数或子例程中提供。

Answer 1

我想应该是这样

f <- function(date1, date2) 
  dbGetQuery(conn, paste0("SELECT A, B as 'Ba', C as 'Ca', D as 'Da', date as 'Date' from database where date>='", date1, "' and date<='", date2, "' "))

查看?paste 获取文档。