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What's the difference between belongs_to and has_one?
...oreign key is. We can say that a User "has" a Profile because the profiles table has a user_id column. If there was a column called profile_id on the users table, however, we would say that a Profile has a User, and the belongs_to/has_one locations would be swapped.
here is a more detailed explanat...
How do I delete a fixed number of rows with sorting in PostgreSQL?
...
You could try using the ctid:
DELETE FROM logtable
WHERE ctid IN (
SELECT ctid
FROM logtable
ORDER BY timestamp
LIMIT 10
)
The ctid is:
The physical location of the row version within its table. Note that although the ctid can be used to locate the...
Do htmlspecialchars and mysql_real_escape_string keep my PHP code safe from injection?
...attack vectors.
Imagine the following SQL:
$result = "SELECT fields FROM table WHERE id = ".mysql_real_escape_string($_POST['id']);
You should be able to see that this is vulnerable to exploit.
Imagine the id parameter contained the common attack vector:
1 OR 1=1
There's no risky chars in the...
How can I create a unique constraint on my column (SQL Server 2008 R2)?
...@WhiteIsland - You should see it in SSMS object Explorer if you expand the table and look under "Keys"
– Martin Smith
Mar 3 '11 at 18:43
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Browsers' default CSS for HTML elements
...}
li { display: list-item }
head { display: none }
table { display: table }
tr { display: table-row }
thead { display: table-header-group }
tbody { display: table-row-group }
tfoot { display: table-footer-group }
col ...
Difference Between One-to-Many, Many-to-One and Many-to-Many?
...one side and City is the many side. There will be a column state_id in the table cities.
In unidirectional, Person class will have List<Skill> skills but
Skill will not have Person person. In bidirectional, both
properties are added and it allows you to access a Person given a
skill( i.e. sk...
How do I add indices to MySQL tables?
I've got a very large MySQL table with about 150,000 rows of data. Currently, when I try and run
7 Answers
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How can I make a div not larger than its contents?
... if someone wonders : one can then center the parent of the table by setting "text-align:center" on it's parent and "text-align:left" on it (e.g. <body style="text-align:center"><span style="text-align:left; display:inline-block;"><table>...</table></span>...
What is DOM Event delegation?
...efinition.
It refers to handling bubbling events from many elements, like table cells, from a parent object, like the table. It can keep the code simpler, especially when adding or removing elements, and saves some memory.
...
How to keep indent for second line in ordered lists via CSS?
...ised to see this hasn't been solved yet. You can make use of the browser's table layout algorithm (without using tables) like this:
ol {
counter-reset: foo;
display: table;
}
ol > li {
counter-increment: foo;
display: table-row;
}
ol > li::before {
content: counter(foo) ...