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SQL “select where not in subquery” returns no results
...east one of the values is NULL.
Suppose we have these data:
common
--
1
3
table1
--
NULL
1
2
LEFT JOIN / IS NULL and NOT EXISTS will return 3, NOT IN will return nothing (since it will always evaluate to either FALSE or NULL).
In MySQL, in case on non-nullable column, LEFT JOIN / IS NULL and...
How to assign a Git SHA1's to a file without Git?
...or example, the hash of an empty file:
sha1("blob 0\0") = "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391"
$ touch empty
$ git hash-object empty
e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
Another example:
sha1("blob 7\0foobar\n") = "323fae03f4606ea9991df8befbb2fca795e648fa"
$ echo "foobar" > foo.tx...
How to use double or single brackets, parentheses, curly braces
...0000000; i++)); do [[ "$i" = 1000 ]]; done
real 0m24.548s
user 0m24.337s
sys 0m0.036s
$ time for ((i=0; i<10000000; i++)); do [ "$i" = 1000 ]; done
real 0m33.478s
user 0m33.478s
sys 0m0.000s
The braces, in addition to delimiting a variable name are used for parameter expansion so ...
How to declare a type as nullable in TypeScript?
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answered Jun 20 '13 at 17:46
Ryan CavanaughRyan Cavanaugh
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Parse rfc3339 date strings in Python? [duplicate]
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3 Answers
3
Active
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How do I search an SQL Server database for a string?
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answered Feb 7 '12 at 23:56
Alex GordonAlex Gordon
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Call apply-like function on each row of dataframe with multiple arguments from each row
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138
You can apply apply to a subset of the original data.
dat <- data.frame(x=c(1,2), y=c(3,4)...
Is there a way to call a stored procedure with Dapper?
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365
In the simple case you can do:
var user = cnn.Query<User>("spGetUser", new {Id = 1},
...
How can I check if a string represents an int, without using try/except?
Is there any way to tell whether a string represents an integer (e.g., '3' , '-17' but not '3.14' or 'asfasfas' ) Without using a try/except mechanism?
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What is the 'instanceof' operator used for in Java?
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Cache Staheli
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answered Sep 5 '11 at 23:37
user166390user166390...