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PostgreSQL naming conventions
Where can I find a detailed manual about PostgreSQL naming conventions? (table names vs. camel case, sequences, primary keys, constraints, indexes, etc...)
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How to get innerHTML of DOMNode?
...se;
$dom->formatOutput = true;
$dom->load($html_string);
$domTables = $dom->getElementsByTagName("table");
// Iterate over DOMNodeList (Implements Traversable)
foreach ($domTables as $table)
{
echo DOMinnerHTML($table);
}
?>
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Condition within JOIN or WHERE
...in join improve performance for large amount of data with properly indexed tables.
– Shahdat
Oct 6 '16 at 15:13
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GROUP BY with MAX(DATE) [duplicate]
...ng to list the latest destination (MAX departure time) for each train in a table, for example :
6 Answers
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MySQL: Large VARCHAR vs. TEXT?
I've got a messages table in MySQL which records messages between users. Apart from the typical ids and message types (all integer types) I need to save the actual message text as either VARCHAR or TEXT. I'm setting a front-end limit of 3000 characters which means the messages would never be inserte...
Reason for Column is invalid in the select list because it is not contained in either an aggregate f
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Suppose I have the following table T:
a b
--------
1 abc
1 def
1 ghi
2 jkl
2 mno
2 pqr
And I do the following query:
SELECT a, b
FROM T
GROUP BY a
The output should have two rows, one row where a=1 and a second row where a=2.
But wha...
Ways to save enums in database
...g.
But if you wanted to really do that, i would create a Suits dimension table:
| Suit | SuitID | Rank | Color |
|------------|--------------|---------------|--------|
| Unknown | 4 | 0 | NULL |
| Heart | 1 | 1 | Red ...
Inserting multiple rows in a single SQL query? [duplicate]
I have multiple set of data to insert at once, say 4 rows. My table has three columns: Person , Id and Office .
4 Answe...
Understanding garbage collection in .NET
...ow. The second duty is however completely invisible. It also generates a table that describes how the local variables inside the method body are used. That table has an entry for each method argument and local variable with two addresses. The address where the variable will first store an object ...
How can I retrieve Id of inserted entity using Entity framework? [closed]
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Let's consider the following scenario:table1 is supposed to generate an @@identity to use it in table2. Both table1 and table2 are supposed to be in the same transaction for e.g. one SaveChange operation must save both table's data. @@identity won't be generated ...