On Tue, 22 Jul 2014, John McKown wrote:
I like to keep the individual lines in my source files relatively
short. Mainly so that I can print them, email them, or display them on
a narrow screen without needing to shift left & right. So, for a
really long character string, such as an SQL query, I do something
like:
query=paste0("select CONVERT(smalldatetime,Int_Start_Date,11) as
Int_Start_Date,",
" CONVERT(smalldatetime,CASE WHEN Int_Start_Time is NULL
then '00:00' ",
"else
LEFT(Int_Start_Time,2)+':'+SUBSTRING(Int_Start_Time,3,2) end +",
"':00', 14) as Int_Start_Time",
", Int_duration, RTRIM(INTTYPE) AS INTTYPE,"
" RTRIM(Int_descr) AS Int_descr",
", RTRIM(INTSUBT) as INTSUBT, "
"INDEXX, RTRIM(Label) AS Label",
", RTRIM(CHANGED) AS CHANGED, "
"RTRIM(ALERT) AS ALERT, "
"RTRIM(RELEASE) AS RELEASE",
" FROM CPINTVL where Int_Start_Date BETWEEN '",
startDateChar,"' and '",endDateChar,"'"
);
So, just as an opinion, is the above "ugly looking" code compared to
just having a really long line? Also, if you/re curious, when I
started most programs were literally punched onto 80 column cards or
displayed on 80 column screens. I still have some damage from this
time (1970s).
This is out there on the frontier of flame war material, but since your
code is missing a couple of commas that are hard to spot I would say it is
rather poorly formatted. My formatting style is not exactly compatible
with most pretty-print styles, but simply recognizing that strings can
span multiple lines can fix a lot of problems for this particular use
case:
query <- paste0( "select CONVERT( smalldatetime
, Int_Start_Date
, 11
) as Int_Start_Dates
, CONVERT( smalldatetime
, CASE WHEN Int_Start_Time is NULL
then '00:00'
else LEFT( Int_Start_Time, 2 )
+ ':'
+ SUBSTRING(Int_Start_Time,3,2)
end
+ ':00'
, 14
) as Int_Start_Time
, Int_duration
, RTRIM( INTTYPE ) AS INTTYPE
, RTRIM( Int_descr ) AS Int_descr
, RTRIM( INTSUBT ) as INTSUBT
, INDEXX
, RTRIM( Label ) AS Label
, RTRIM( CHANGED ) AS CHANGED
, RTRIM( ALERT ) AS ALERT
, RTRIM( RELEASE ) AS RELEASE
FROM CPINTVL
where Int_Start_Date BETWEEN '"
, startDateChar
, "' and '"
, endDateChar
,"'"
);
By the way... parameterized queries are safer (no SQL injection) and
faster-executing (well, for repeated use) than pasting input text into
query text.
Another approach is to store really long strings in data files.
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