r - 'T' & 'F' 从数据库中读取为 True 和 False

Question

我需要使用 RODBC sqlQuery 函数从其中一列包含“T”和“F”值的数据库中读取数据。然而，我的结果不断出现“真”和“假”。我找到了以下阅读 csv 文件的帖子。 sqlQuery 函数是否有类似的解决方法？

read.table reads "T" as TRUE and "F" as FALSE, how to avoid?

编辑:这是我按照评论中的要求运行的代码。如果不访问数据库，它将无法执行......

conn = odbcConnect(dataBaseName)
results = sqlQuery(conn, paste0("select ID, andate, antime from table.e4 where ticker in (",paste(shQuote(IDvector, type = "sh"), collapse = ', '),");"))
close(conn)

ID是包含'T'和'Fs的字段

Answer 1

sqlQuery 函数有 as.is 选项，来自 the RODBC manual :

as.is which (if any) columns returned as character should be converted to another type? Allowed values are as for read.table. See ‘Details’.

Details
... if as.is is true for a column, it is returned as a character vector. Otherwise (where detected) date, datetime and timestamp values are converted to the "Date" or "POSIXct" class. ...