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A Task's exception(s) were not observed either by Waiting on the Task or accessing its Exception pro
What does this mean and how to resolve it?
3 Answers
3
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How to get the last character of a string in a shell?
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echo "${str:$i:1}"
Otherwise, bash expands the variable and in this case does globbing before printing out. It is also better to quote the parameter to the script (in case you have a matching filename):
sh lash_ch.sh 'abcde*'
Also see the order of expansions in the bash reference manual. Variable...
How to get a specific version of a file in Mercurial?
...ituting revisionid and filename of course) which will output the file to stdout, suitable for redirecting anyplace you'd like.
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Real life example, when to use OUTER / CROSS APPLY in SQL
...y_plan(qs.plan_handle)
3) Reusing a column alias
SELECT number,
doubled_number,
doubled_number_plus_one
FROM master..spt_values
CROSS APPLY (SELECT 2 * CAST(number AS BIGINT)) CA1(doubled_number)
CROSS APPLY (SELECT doubled_number + 1) CA2(doubled_number_plus_one)
4) Unpivoti...
Where does gcc look for C and C++ header files?
On a Unix system, where does gcc look for header files?
9 Answers
9
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How to remove unwanted space between rows and columns in table?
How do I remove the extra space between the rows and columns in the table.
14 Answers
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How is Pythons glob.glob ordered?
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Yes, unless it does a special effort, it will simply show the entries as the operating system provides it. The same as the command "find" in Unix, it just dumps the entries in the order they come from the data structure used by the underly...
How to create a drop shadow only on one side of an element?
Is there a way to drop the shadow only on the bottom?. I have a menu with 2 images next to each other. I don't want a right shadow because it overlaps the right image. I don't like to use images for this so is there a way to drop it only on the bottom like:
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Is there a timeout for idle PostgreSQL connections?
...stgreSQL to boot all other connections off a PostgreSQL database, see: How do I detach all other users from a postgres database? and How to drop a PostgreSQL database if there are active connections to it? . The latter shows a better query.
For setting timeouts, as @Doon suggested see How to close ...
Summarizing multiple columns with dplyr? [duplicate]
... 2 3.03 3.04 2.97 2.87
#> 3 3 2.85 2.95 2.95 3.06
Also don't forget about data.table (use keyby to sort sort groups):
library(data.table)
setDT(df)[, lapply(.SD, mean), keyby = grp]
#> grp a b c d
#> 1: 1 3.079412 2.979412 2.979412 2.914706
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