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How to best display in Terminal a MySQL SELECT returning too many fields?
...mple, if you define the delimiter as X, you will be unable to use the word INDEX in statements."
– Benjamin
Oct 9 '15 at 8:57
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Numpy argsort - what is it doing?
...ocumentation
Returns the indices that would sort an array.
2 is the index of 0.0.
3 is the index of 0.1.
1 is the index of 1.41.
0 is the index of 1.48.
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How to convert current date into string in java?
... and the answer right below for the timestring. C:
– php_coder_3809625
Jul 13 '16 at 13:54
@Ian Purton Is string date ...
SQL - many-to-many table primary key
...r col1 and col2 values in the referenced tables are unique) and a separate index on (col2,col1) will catch those cases where the opposite order would execute faster. The surrogate is a waste of space.
You won't need indexes on the individual columns since the table should only ever be used to join ...
setup.py examples?
...rial. Try also just browsing through Python packages on the Python Package Index. Just download the tarball, unpack it, and have a look at the setup.py file. Or even better, only bother looking through packages that list a public source code repository such as one hosted on GitHub or BitBucket. You'...
How to send and retrieve parameters using $state.go toParams and $stateParams?
...oller'
})
.state('view', {
templateUrl: 'overview',
params: ['index', 'anotherKey'],
controller: 'overviewController'
})
So also you should pass toParams as array like this:
params = { 'index': 123, 'anotherKey': 'This is a test' }
paramsArr = (val for key, val of params)
$state...
How do I discard unstaged changes in Git?
How do I discard changes in my working copy that are not in the index?
36 Answers
36
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How to concatenate columns in a Postgres SELECT?
...catenated to NULL is NULL. If NULL values can be involved and the result shall not be NULL, use concat_ws() to concatenate any number of values (Postgres 9.1 or later):
SELECT concat_ws(', ', a, b) AS ab FROM foo;
Or concat() if you don't need separators:
SELECT concat(a, b) AS ab FROM foo;
No...
Ways to iterate over a list in Java
..., only if you do it through the remove method of the iterator itself. With index-based iteration, you are free to modify the list in any way. However, adding or removing elements that come before the current index risks having your loop skipping elements or processing the same element multiple times...
PostgreSQL: How to make “case-insensitive” query
...ny function) on the predicate columns--in this case "name"--will cause any indexes to no longer be seekable. If this is a large or frequently queried table, that could cause trouble. Case-insensitive collation, citext, or a function-based index will improve performance.
– Jorda...