Question

如果我的大脑运作良好，我一直在努力解决一个似乎有简单解决方案的问题。我必须通过更改from_date和to_date的值，每月在SQL Server数据库中运行SQL存储过程。我无法弄清楚如何更改带引号的字符串中的值。这是我使用paste（）的代码，它给了我错误。

to_date <- '20160229'
from_date <- '20160201'
require(RODBC)
dWA_ABCD_BT_D <-  odbcDriverConnect('driver={SQL Server}; server=ABCD;        database=dWA_ABCD_BT_D; trusted_connection=true')
sens.raw <- sqlQuery( dWA_ABCD_BT_D,   "exec m_rawData_sens @from_dt = '20140301' , @to_dt = '20160229'  "  )
# Here the code using paste() that never worked-------------
sens.raw <- sqlQuery( dWA_ABCD_BT_D, paste("exec", "m_rawData_sens","@from_dt =", sQuote(from_date) , ",", "@to_dt =",  sQuote(to_date) , sep="  "  ))
# also tried without sQuote()
sens.raw <- sqlQuery( dWA_ABCD_BT_D, paste("exec", "m_rawData_sens","@from_dt =", from_date , ",", "@to_dt =",  to_date , sep="  "  ))
odbcClose(dWA_ABCD_BT_D)

这是我的错误消息

[1] "42000 102 [Microsoft][ODBC SQL Server Driver][SQL Server]Incorrect syntax near '‘'."                           
[2] "[RODBC] ERROR: Could not SQLExecDirect 'exec  m_rawData_sens  @from_dt =  ‘20160201’  ,  @to_dt =  ‘20160229’'"

我必须每月更改from_date和to_date，以便从R中执行16次SP执行。任何帮助都得到R社区的赞赏....谢谢

Answer 1

从?sQuote()使用ASCII 0x27单引号，您可能必须将此行放在paste()之前：

options( useFancyQuotes=FALSE)

另一种解决方法是将单引号直接放在字符串中，但使用paste0()来避免引号和值之间的空格：

paste0("exec ", "m_rawData_sens ","@from_dt='", from_date , "', ", "@to_dt ='",  to_date, "'"  )

将引用字符串中的值切换为运行函数

1 个答案: