How to use a variable date when running a db2 command in a shell script?

Question

I need to use a date variable in a select, like bellow, but I'm getting this error: Expected tokens may include: "". SQLSTATE=42601

How can use these variables in a shell script?

day0_T1=`TZ=CST+12 date +"%Y-%m-%d %T"`
day0_T0=`TZ=CST+24 date +"%Y-%m-%d %T"`
dayn_Tn=`TZ=CST+n date +"%Y-%m-%d %T"`

db2 connect to BD
db2 "/path/result.tmp  OF DEL MODIFIED BY COLDEL; decplusblank striplzeros
select count(*),user from table1
and close_datetime between cast(date('$day0_T0') as timestamp) AND cast(date('$day0_T1') as timestamp)
and task = 'task1' 
group by user
with ur"
db2 terminate

Answer 1

Shell quotes typically delimit arguments or escape other special shell characters from shell interpretation. You can contain (and therefore escape) different kinds of shell-quotes within other kinds based on various rules:

• "''''" - a soft-quoted string can contain any number of hard-quotes.
• "\"" - a \ backslash can escape a "soft-quote within a "soft-quoted string.
• In this context a \\backslash also escapes itself, the \$expansion token, and \newlines as noted below, but is otherwise treated literally.
• "${expand} and then some" - a soft-quoted string can contain an interpreted shell $expansion.
• '"\' - a 'hard-quoted string can contain any character other than a 'hard-quote.
• \ - an unquoted backslash will escape any following character for literal interpretation - even another backslash - excepting a \newline.
• In a \\newline case both the \ backslash and the \newline are completely removed from the resulting interpreted command. ${parameter+expand "$parameter"} - quotes resulting from a shell expansion almost never serve as delimiter markers excepting a few special cases. I won't venture to describe these further here.

Test:

root@onare:/home/onare# echo $day0_T1
2015-07-16 14:10:44
root@onare:/home/onare# db2="something '${day0_T1}'"
root@onare:/home/onare# echo $db2
something '2015-07-16 14:10:44'
root@onare:/home/onare#