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What integer hash function are good that accepts an integer hash key?
...hich is not uncommon), their hashes will be too. This is a problem in hash tables - you can end up with only 1/2 or 1/4 of the buckets being used.
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Update multiple rows in same query using PostgreSQL
...
You can also use update ... from syntax and use a mapping table. If you want to update more than one column, it's much more generalizable:
update test as t set
column_a = c.column_a
from (values
('123', 1),
('345', 2)
) as c(column_b, column_a)
where c.column_b = t.c...
How to remove unwanted space between rows and columns in table?
How do I remove the extra space between the rows and columns in the table.
14 Answers
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How to implement a rule engine?
I have a db table that stores the following:
10 Answers
10
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MySQL “NOT IN” query
I wanted to run a simple query to throw up all the rows of Table1 where a principal column value is not present in a column in another table ( Table2 ).
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PHP code to convert a MySQL query to CSV [closed]
...MINATED BY ',' OPTIONALLY ENCLOSED BY '"'
LINES TERMINATED BY "\n"
FROM my_table;
(the documentation for this is here: http://dev.mysql.com/doc/refman/5.0/en/select.html)
or:
$select = "SELECT * FROM table_name";
$export = mysql_query ( $select ) or die ( "Sql error : " . mysql_error( ) );
$fi...
In jQuery, how do I get the value of a radio button when they all have the same name?
...dflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<table>
<tr>
<td>Sales Promotion</td>
<td><input type="radio" name="q12_3" value="1">1</td>
<td><input type="radio" name="q12_3" value="2">2</td>
...
Which method performs better: .Any() vs .Count() > 0?
...esh look on the problem.
Testing env:
EF 6.1.3, SQL Server, 300k records
Table model:
class TestTable
{
[Key]
public int Id { get; set; }
public string Name { get; set; }
public string Surname { get; set; }
}
Test code:
class Program
{
static void Main()
{
usi...
Efficiently updating database using SQLAlchemy ORM
...ows one by one.
Instead you should do this:
session.execute(update(stuff_table, values={stuff_table.c.foo: stuff_table.c.foo + 1}))
session.commit()
This will execute as one query as you would expect, and because at least the default session configuration expires all data in the session on commi...
SQL Server: Filter output of sp_who2
...
You could try something like
DECLARE @Table TABLE(
SPID INT,
Status VARCHAR(MAX),
LOGIN VARCHAR(MAX),
HostName VARCHAR(MAX),
BlkBy VARCHAR(MAX),
DBName VARCHAR(MAX),
Command VARCHAR(MAX),
CPUTime INT...