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How to generate a create table script for an existing table in phpmyadmin?
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@Davos use this, show create table database_name.tablename.
– Fahad Anjum
Apr 20 '18 at 9:21
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Summarizing multiple columns with dplyr? [duplicate]
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The dplyr package contains summarise_all for this aim:
library(dplyr)
df %>% group_by(grp) %>% summarise_all(list(mean))
#> # A tibble: 3 x 5
#> grp a b c d
#> <int> <dbl> <dbl> <dbl> <dbl>
#>...
.NET data structures: ArrayList, List, HashTable, Dictionary, SortedList, SortedDictionary — Speed,
...d Visual Basic books talk about them to a certain extent, but they never really go into any real detail.
13 Answers
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How to convert 'binary string' to normal string in Python3?
For example, I have a string like this(return value of subprocess.check_output ):
3 Answers
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Difference between Destroy and Delete
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Basically destroy runs any callbacks on the model while delete doesn't.
From the Rails API:
ActiveRecord::Persistence.delete
Deletes the record in the database and freezes this instance to reflect that no changes should be ...
How to convert an Int to a String of a given length with leading zeros to align?
...this Q&A becomes the canonical compendium,
scala> import java.text._
import java.text._
scala> NumberFormat.getIntegerInstance.asInstanceOf[DecimalFormat]
res0: java.text.DecimalFormat = java.text.DecimalFormat@674dc
scala> .applyPattern("0000000")
scala> res0.format(123)
res2: S...
Scale image to fit a bounding box
...ed answer, the answer below is more accurate and is currently supported in all browsers if you have the option of using a background image.
No, there is no CSS only way to do this in both directions. You could add
.fillwidth {
min-width: 100%;
height: auto;
}
To the an element to always...
How does Rails keep track of which migrations have run for a database?
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Rails creates a table in your database called schema_migrations to keep track of which migrations have run.
The table contains a single column, version. When Rails runs a migration, it takes the leading digits in the migration's file name and inserts a row for that "version",...
Sending an Intent to browser to open specific URL [duplicate]
... this line in try/catch block to prevent app crash. This could happen if really no browser app installed on target device (yeah, shoot happens) also it could be that your app was forbidden to start a browser using restrict profiles.
– Stan
Jun 12 '15 at 18:10
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Why are Oracle table/column/index names limited to 30 characters?
..., but there is always a case that turns up where we hit this limit - especially in naming foreign keys.
10 Answers
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