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Grant **all** privileges on database
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@Romain you are not really bringing alot to the table here - i don't name my users myuser - the questioner was simply using a username as an example - i used the same example username for consistency.
– diagonalbatman
Feb 16 '11 at 13...
Python Pandas merge only certain columns
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This is to merge selected columns from two tables.
If table_1 contains t1_a,t1_b,t1_c..,id,..t1_z columns,
and table_2 contains t2_a, t2_b, t2_c..., id,..t2_z columns,
and only t1_a, id, t2_a are required in the final table, then
mergedCSV = table_1[['t1_a','id']].m...
How to create CSV Excel file C#? [closed]
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Its best example...but how can i add two table in single file,means i have a one table of two rows and other table is 10 rows and both have unique column name.I want to add two rows table on top and after gap of two lines i want to add second table.
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Why do my list item bullets overlap floating elements
...e CSS below to make the list work alongside the floated content.
display: table; works alongside floated content (filling the gap) but without hiding content behind it. Much like a table does :-)
.img {
float: left;
}
.table {
display: table;
}
<img class="img" src="https://via....
Automatically deleting related rows in Laravel (Eloquent ORM)
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You can actually set this up in your migrations:
$table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
Source: http://laravel.com/docs/5.1/migrations#foreign-key-constraints
You may also specify the desired action for the "on delete...
Difference between HashSet and HashMap?
... functions. This is critical because HashMap uses power-of two length hash tables." weblogs.java.net/blog/2005/06/18/hashmap-implementation - however, if you look at the doc you'll see that this hash distributes things over "buckets", so in the end I believe two things can get mapped the same bucket...
@UniqueConstraint and @Column(unique = true) in hibernate annotation
...hould have unique values. The same aplies for group.
On the other hand,
@Table(
name = "product_serial_group_mask",
uniqueConstraints = {@UniqueConstraint(columnNames = {"mask", "group"})}
)
Implies that the values of mask + group combined should be unique. That means you can have, for ex...
PostgreSQL Crosstab Query
... create crosstab queries in PostgreSQL?
For example I have the following table:
6 Answers
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When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
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GO is like the end of a script.
You could have multiple CREATE TABLE statements, separated by GO. It's a way of isolating one part of the script from another, but submitting it all in one block.
BEGIN and END are just like { and } in C/++/#, Java, etc.
They bound a logical block of ...
Rails where condition using NOT NIL
...udes(:bar).where.not(bars: { id: nil })
When working with scopes between tables, I prefer to leverage merge so that I can use existing scopes more easily.
Foo.includes(:bar).merge(Bar.where.not(id: nil))
Also, since includes does not always choose a join strategy, you should use references here...