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What can you use Python generator functions for?
...uld like to update Alexa rank for each domain.
First thing you need is to select your domain names from the database.
Let's say your table name is domains and column name is domain.
If you use SELECT domain FROM domains it's going to return 100 million rows which is going to consume lot of memory...
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)...
How do I change the data type for a column in MySQL?
...n type to another type, you can generate queries using a query like this:
select distinct concat('alter table ',
table_name,
' modify ',
column_name,
' <new datatype> ',
if(is_nu...
Multiple queries executed in java in single statement
...s wondering if it is possible to execute something like this using JDBC.
"SELECT FROM * TABLE;INSERT INTO TABLE;"
Yes it is possible. There are two ways, as far as I know. They are
By setting database connection property to allow multiple queries,
separated by a semi-colon by default.
By callin...
+ 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...
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...
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;
...
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...