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+ operator for array in PHP?
...and array)
)
So the logic of + is equivalent to the following snippet:
$union = $array1;
foreach ($array2 as $key => $value) {
if (false === array_key_exists($key, $union)) {
$union[$key] = $value;
}
}
If you are interested in the details of the C-level implementation head t...
Throw an error in a MySQL trigger
... trigger_test values (1), (-1), (2); -- everything fails as one row is bad
select * from trigger_test;
insert into trigger_test values (1); -- succeeds as expected
insert into trigger_test values (-1); -- fails as expected
select * from trigger_test;
...
Having both a Created and Last Updated timestamp columns in MySQL 4.0
...dated) values(null, null);
Query OK, 1 row affected (0.06 sec)
mysql> select * from test_table;
+----+---------------------+---------------------+
| id | stamp_created | stamp_updated |
+----+---------------------+---------------------+
| 2 | 2009-04-30 09:44:35 | 2009-04-30 09:4...
SQL select only rows with max value on a column [duplicate]
...ce...
All you need is a GROUP BY clause with the MAX aggregate function:
SELECT id, MAX(rev)
FROM YourTable
GROUP BY id
It's never that simple, is it?
I just noticed you need the content column as well.
This is a very common question in SQL: find the whole data for the row with some max value ...
MySQL Select Query - Get only first 10 characters of a value
...
Using the below line
SELECT LEFT(subject , 10) FROM tbl
MySQL Doc.
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MySQL Query - Records between Today and Last 30 Days
...
You need to apply DATE_FORMAT in the SELECT clause, not the WHERE clause:
SELECT DATE_FORMAT(create_date, '%m/%d/%Y')
FROM mytable
WHERE create_date BETWEEN CURDATE() - INTERVAL 30 DAY AND CURDATE()
Also note that CURDATE() returns only the DATE portion...
MySQL/SQL: Group by date only on a Datetime column
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Cast the datetime to a date, then GROUP BY using this syntax:
SELECT SUM(foo), DATE(mydate) FROM a_table GROUP BY DATE(a_table.mydate);
Or you can GROUP BY the alias as @orlandu63 suggested:
SELECT SUM(foo), DATE(mydate) DateOnly FROM a_table GROUP BY DateOnly;
Though I don't think...
How to truncate a foreign key constrained table?
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As per mysql documentation, TRUNCATE cannot be used on tables with foreign key relationships. There is no complete alternative AFAIK.
Dropping the contraint still does not invoke the ON DELETE and ON UPDATE.
The only solution I can...
What is the simplest SQL Query to find the second largest value?
...
SELECT MAX( col )
FROM table
WHERE col < ( SELECT MAX( col )
FROM table )
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MySQL Select minimum/maximum among two (or more) given values
Is it possible to SELECT the minimum or maximum among two or more values. I'd need something like this:
4 Answers
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