Yes, you are right... the other is definitely not a valid query.

thanks


On Tue, Sep 17, 2013 at 11:22 AM, Jeff Newmiller
<jdnewmil@dcn.davis.ca.us>wrote:

>
>  id <- c("21328","78789D")
>>
>> query <- paste(paste("select * from tbl_user where student_id = ",
>>
> id,sep=""), " order by date_time", sep="")
>
>> query
>>
> [1] "select * from tbl_user where student_id = 21328 order by date_time"
> [2] "select * from tbl_user where student_id = 78789D order by date_time"
>
> Now, does the second string look like valid SQL to you? In particular, the
> 78789D is a problem. On the other hand...
>
>
>  query <- paste(paste("select * from tbl_user where student_id = '",
>>
> id,sep=""), "' order by date_time", sep="")
>
>> query
>>
> [1] "select * from tbl_user where student_id = '21328' order by date_time"
> [2] "select * from tbl_user where student_id = '78789D' order by date_time"
>
> As others have pointed out, in this case escaping does not appear to be
> key to getting valid SQL syntax... but looking at the query before shipping
> it off to a database engine seems to me to be an obvious technique you
> should learn.
>
>
> On Tue, 17 Sep 2013, srecko joksimovic wrote:
>
>  There is no difference, the same query structure is in the both
>> cases:"6683"
>> "character"
>> "character"
>> "select * from students where student_id = 6683 order by date_time"
>> "4738D"
>> "character"
>> "character"
>> "select * from students where student_id = 4738D order by date_time"
>>
>> and still is the same error
>>
>>
>> On Tue, Sep 17, 2013 at 9:47 AM, srecko joksimovic
>> <sreckojoksimovic@gmail.com> wrote:
>>       thanks, Jeff,
>> good point... I'll try that
>>
>>
>> On Tue, Sep 17, 2013 at 9:43 AM, Jeff Newmiller
>> <jdnewmil@dcn.davis.ca.us> wrote:
>>       Why don't you print the 'query' variable with each id
>>       value and consider what the SQL syntax is for number and
>>       string literals. Then study the use of escaping in strings
>>       ("\\") to fix the query.
>> ------------------------------**------------------------------**
>> ---------------
>>
>>       Jeff Newmiller                        The     .....
>>       .....  Go Live...
>>       DCN:<jdnewmil@dcn.davis.ca.us>        Basics: ##.#.
>>       ##.#.  Live Go...
>>                                             Live:   OO#.. Dead:
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>>
>>       Sent from my phone. Please excuse my brevity.
>>
>>       srecko joksimovic <sreckojoksimovic@gmail.com> wrote:
>>       >Hi,
>>       >
>>       >when I generate query using sqldf library, like this:
>>       >query = paste(paste("select * from tbl_user where
>>       student_id = ", id,
>>       >                sep=""), " order by date_time", sep="")
>>       >
>>       >student <- sqldf(query)
>>       >
>>       >everything works fine in case the id is "21328", "82882",
>>       or something
>>       >like
>>       >that. But, when id is something like "78789D", there is
>>       an error:
>>       >Error in sqliteExecStatement(con, statement, bind.data) :
>>       >  RS-DBI driver: (error in statement: unrecognized token:
>>       "78789D")
>>       >
>>       >I tried replacing single quotes with double, but it still
>>       doesn't
>>       >work...
>>       >
>>       >thanks,
>>       >Srecko
>>       >
>> >       [[alternative HTML version deleted]]
>> >
>> >_____________________________**_________________
>> >R-help@r-project.org mailing list
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>> >PLEASE do read the posting guide
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>> >and provide commented, minimal, self-contained, reproducible
>> code.
>>
>>
>>
>>
>>
>>
> ------------------------------**------------------------------**
> ---------------
> Jeff Newmiller                        The     .....       .....  Go Live...
> DCN:<jdnewmil@dcn.davis.ca.us>        Basics: ##.#.       ##.#.  Live
> Go...
>                                       Live:   OO#.. Dead: OO#..  Playing
> Research Engineer (Solar/Batteries            O.O#.       #.O#.  with
> /Software/Embedded Controllers)               .OO#.       .OO#.  rocks...1k
> ------------------------------**------------------------------**
> ---------------
>

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