Question

我需要检查我与数据库的连接，是否已过期：当我尝试执行查询时，我得到了这样的错误

> dbGetQuery(con,"select * from users limit 1")
Error in postgresqlExecStatement(conn, statement, ...) : 
  RS-DBI driver: (could not run statement: could not receive data from server: Software caused connection abort (0x00002745/10053)
)
NULL
Warning message:
In postgresqlQuickSQL(conn, statement, ...) :
  Could not create executeselect * from users limit 1

好的，我需要类似“如果错误然后打印（”连接已过期“）”。我试图解决这个问题：

> class(try(dbGetQuery(con,"select * from users limit 1"), silent = T))
Error in postgresqlExecStatement(conn, statement, ...) : 
  RS-DBI driver: (could not run statement: could not receive data from server: Software caused connection abort (0x00002745/10053)
)
[1] "NULL"
Warning message:
In postgresqlQuickSQL(conn, statement, ...) :
  Could not create executeselect * from users limit 1

再次收到此错误并发出警告。尝试表达式的类是“NULL”，而不是“try-error”。但是当我这样做时：

> class(try(log("hi"), silent = T))
[1] "try-error"

我没有错误和尝试错误类

为什么？

UPD。通过

解决了这个问题

>options(warn = 2, show.error.messages = F)

然后

class(try(dbGetQuery(con,"select * from users limit 1"), silent = T))
[1] "try-error"

R中无法获得“try-error”类

0 个答案: