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What is the reason not to use select *?
I've seen a number of people claim that you should specifically name each column you want in your select query.
20 Answers
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minimum double value in C/C++
Is there a standard and/or portable way to represent the smallest negative value (e.g. to use negative infinity) in a C(++) program?
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Replace spaces with dashes and make all letters lower-case
...games"
Notice the g flag on the RegExp, it will make the replacement globally within the string, if it's not used, only the first occurrence will be replaced, and also, that RegExp will match one or more white-space characters.
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On duplicate key ignore? [duplicate]
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Would suggest NOT using INSERT IGNORE as it ignores ALL errors (ie its a sloppy global ignore).
Instead, since in your example tag is the unique key, use:
INSERT INTO table_tags (tag) VALUES ('tag_a'),('tab_b'),('tag_c') ON DUPLICATE KEY UPDATE tag=tag;
on duplicate key pro...
How to empty (clear) the logcat buffer in Android [duplicate]
...rooted buffers (main, system ..etc).
adb logcat -c
If you want to clear all the buffers (like radio, kernel..etc), Please use the following commands
adb root
adb logcat -b all -c
or
adb root
adb shell logcat -b all -c
Use the following commands to know the list of buffers that device supp...
Laravel Eloquent groupBy() AND also return count of each group
...: Total Records: 10; Internet Explorer 8: 2; Chrome 25: 4; Firefox 20: 4. (All adding up to 10)
10 Answers
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Logcat not displaying my log calls
... wanted to learn how to debug my apps. I can't seem to have my Log.i|d|v calls displayed in the LogCat.
31 Answers
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Remove duplicated rows
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Do note that this will remove all the columns except for the three first ones.
– GuillaumeL
Apr 1 '19 at 13:47
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How to select date from datetime column?
...20' has performance issues. As stated here:
it will calculate DATE() for all rows, including those that don't match.
it will make it impossible to use an index for the query.
Use BETWEEN or >, <, = operators which allow to use an index:
SELECT * FROM data
WHERE datetime BETWEEN '2009-10-...
Separate Back Stack for each tab in Android using Fragments
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The framework won't currently do this for you automatically. You will need to build and manage your own back stacks for each tab.
To be honest, this seems like a really questionable thing to do. I can't imagine it resulting in a decent UI -- if the back key is going to do diff...