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Deleting all rows from Cassandra cql table [duplicate]
Is there a command to all the rows present in a cql table in cassandra like the one in sql?
1 Answer
...
How does a PreparedStatement avoid or prevent SQL injection?
...);
If "user" came from user input and the user input was
Robert'); DROP TABLE students; --
Then in the first instance, you'd be hosed. In the second, you'd be safe and Little Bobby Tables would be registered for your school.
...
How to return result of a SELECT inside a function in PostgreSQL?
...ERY:
CREATE OR REPLACE FUNCTION word_frequency(_max_tokens int)
RETURNS TABLE (txt text -- also visible as OUT parameter inside function
, cnt bigint
, ratio bigint) AS
$func$
BEGIN
RETURN QUERY
SELECT t.txt
, count(*) AS cnt -- co...
Storyboard warning: prototype table cells must have reuse identifiers
I am getting this warning from storyboard - prototype table cells must have reuse identifiers.
11 Answers
...
What is the difference between bottom-up and top-down?
...ds the root.
Tabulation - You can also think of dynamic programming as a "table-filling" algorithm (though usually multidimensional, this 'table' may have non-Euclidean geometry in very rare cases*). This is like memoization but more active, and involves one additional step: You must pick, ahead of...
Remove columns from dataframe where ALL values are NA
... function to reduce the size. The answer bellow using Filter or using data.table will help your memory usage.
– mtelesha
Dec 9 '15 at 15:21
3
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PostgreSQL - max number of parameters in “IN” clause?
... possible if the inputs are all scalars (no RowExprs) and there is a
* suitable array type available. If not, we fall back to a boolean
* condition tree with multiple copies of the lefthand expression.
* Also, any IN-list items that contain Vars are handled as separate
* boolean conditions, bec...
Using group by on multiple columns
...one group.
To illustrate using an example, let's say we have the following table, to do with who is attending what subject at a university:
Table: Subject_Selection
+---------+----------+----------+
| Subject | Semester | Attendee |
+---------+----------+----------+
| ITB001 | 1 | John ...
What is the best way to use a HashMap in C++?
...rdered map insert and access is in O(1). It is just another name for a hashtable.
An example with (ordered) std::map:
#include <map>
#include <iostream>
#include <cassert>
int main(int argc, char **argv)
{
std::map<std::string, int> m;
m["hello"] = 23;
// check if ke...
Where do you store your salt strings?
...
The point of rainbow tables is that they're created in advance and distributed en masse to save calculation time for others - it takes just as long to generate rainbow tables on the fly as it would to just crack the password+salt combination dire...