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MySQL error: key specification without a key length
...ified implicitly within a bracket right after its declaration, i.e VARCHAR(200) will limit it to 200 characters long only.
Sometimes, even though you don’t use TEXT or BLOB related type in your table, the Error 1170 may also appear. It happens in a situation such as when you specify VARCHAR colum...
Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
...tree (instead of relying of a "well known value").
Note: Git 2.25.1 (Feb. 2020) proposes in commit 9c8a294:
empty_tree=$(git mktree </dev/null)
# Windows:
git mktree <NUL
And adds:
As a historical note, the function now known as repo_read_object_file() was taught the empty tree in 3462...
Select rows of a matrix that meet a condition
...
m <- matrix(1:20, ncol = 4)
colnames(m) <- letters[1:4]
The following command will select the first row of the matrix above.
subset(m, m[,4] == 16)
And this will select the last three.
subset(m, m[,4] > 17)
The result will b...
Maximum concurrent Socket.IO connections
...e library.
– DeeperID
Feb 27 '15 at 20:47
2
@JAM Did you ever discover why your web sockets were ...
Is there a way to get version from package.json in nodejs code?
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answered Apr 20 '16 at 3:24
Patrick Lee ScottPatrick Lee Scott
6,38211 gold badge2929 silver badges4242 bronze badges
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Is it possible to run JavaFX applications on iOS, Android or Windows Phone 8?
...ed and what was the state of JavaFX on embedded and mobile in beginning of 2014. But, a lot has changed since then and the users who stumble on this thread do not get the updated information.
Most of my points are related to Invariant's answer, so I would suggest to go through it first.
Current St...
Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a con
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answered Sep 19 '08 at 20:04
KeithBKeithB
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Why does csvwriter.writerow() put a comma after each character?
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Laurence GonsalvesLaurence Gonsalves
120k2929 gold badges213213 silver badges259259 bronze badges
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Does MySQL foreign_key_checks affect the entire database?
...need to add the keys while checking is on."
– user2782001
Mar 30 '16 at 18:20
4
Let's say you hav...
Is there an alternative sleep function in C to milliseconds?
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Bernardo RamosBernardo Ramos
2,4212020 silver badges2020 bronze badges
3
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