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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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XAMPP - MySQL shutdown unexpectedly
...Windows has built-in folder versioning — right click on /mysql/data/ and select Restore previous versions. You can then delete the current contents of the folder and replace it with the older version's contents.
Addendum: To ensure that you don't forget to run XAMPP as an administrator you can ri...
How do I add more members to my ENUM-type column in MySQL?
... do not appear in your ENUM. What is the output of the following command?
SELECT DISTINCT country FROM carmake;
ANOTHER EDIT: What is the output of the following command?
SHOW VARIABLES LIKE 'sql_mode';
Is it STRICT_TRANS_TABLES or STRICT_ALL_TABLES? That could lead to an error, rather than the ...
Can someone give an example of cosine similarity, in a very simple, graphical way?
...e1)
counter2 = Counter(iterable2)
all_items = set(counter1.keys()).union(set(counter2.keys()))
vector1 = [counter1[k] for k in all_items]
vector2 = [counter2[k] for k in all_items]
return vector1, vector2
def cosim(v1, v2):
dot_product = sum(n1 * n2 for n1, n2 in zip(v1, v2)...
+ 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...
What is the difference between single and double quotes in SQL?
...ould be more readable as product_id, so you use either of the following:
SELECT PRODUCT.id AS product_id
SELECT PRODUCT.id 'product_id'
Either works in Oracle, SQL Server, MySQL… but I know some have said that the TOAD IDE seems to give some grief when using the single quotes approach.
You do...
Using LIMIT within GROUP BY to get N results per group?
...to get all years into a single column, grouped by id and ordered by rate:
SELECT id, GROUP_CONCAT(year ORDER BY rate DESC) grouped_year
FROM yourtable
GROUP BY id
Result:
-----------------------------------------------------------
| ID | GROUPED_YEAR |...
MySQL stored procedure vs function, which would I use when?
...d procedures with ordinary SQL, whilst with stored function you can.
e.g. SELECT get_foo(myColumn) FROM mytable is not valid if get_foo() is a procedure, but you can do that if get_foo() is a function. The price is that functions have more limitations than a procedure.
...
通信连接组件 · App Inventor 2 中文网
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JOIN queries vs multiple queries
...han several queries? (You run your main query, and then you run many other SELECTs based on the results from your main query)
...