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SQL Server: Maximum character length of object names
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Yes, it is 128, except for temp tables, whose names can only be up to 116 character long.
It is perfectly explained here.
And the verification can be easily made with the following script contained in the blog post before:
DECLARE @i NVARCHAR(800)
SELECT ...
differentiate null=True, blank=True in django
...e)
The database fields created for PostgreSQL 9.4 are :
CREATE TABLE Test (
id serial NOT NULL,
"charNull" character varying(10),
"charBlank" character varying(10) NOT NULL,
"charNullBlank" character varying(10),
"intNull" in...
Export and Import all MySQL databases at one time
...-databases > alldb.sql
mysqldump -u root -p --all-databases --skip-lock-tables > alldb.sql
Import:
mysql -u root -p < alldb.sql
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Delete/Reset all entries in Core Data?
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You can delete the SQLite file - but I choose to do it by purging the tables individually with a functions:
- (void) deleteAllObjects: (NSString *) entityDescription {
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription enti...
Pandas count(distinct) equivalent
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I believe this is what you want:
table.groupby('YEARMONTH').CLIENTCODE.nunique()
Example:
In [2]: table
Out[2]:
CLIENTCODE YEARMONTH
0 1 201301
1 1 201301
2 2 201301
3 1 201302
4 2 ...
How can I prevent the scrollbar overlaying content in IE10?
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This issue is also happening with Datatables on Bootstrap 4. Mi solution was:
Checked if the ie browser is opening.
Replaced table-responsive class for table-responsive-ie class.
CSS:
.table-responsive-ie {
display: block;
width: 100%;
overflow-x: auto;}
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Which rows are returned when using LIMIT with OFFSET in MySQL?
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OFFSET is nothing but a keyword to indicate starting cursor in table
SELECT column FROM table LIMIT 18 OFFSET 8 -- fetch 18 records, begin with record 9 (OFFSET 8)
you would get the same result form
SELECT column FROM table LIMIT 8, 18
visual representation (R is one record in the ...
How can i query for null values in entity framework?
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Workaround for Linq-to-SQL:
var result = from entry in table
where entry.something.Equals(value)
select entry;
Workaround for Linq-to-Entities (ouch!):
var result = from entry in table
where (value == null ? entry.something == null : entr...
Performance of FOR vs FOREACH in PHP
..._arr1 = array();
$test_arr2 = array();
$test_arr3 = array();
// hash tables
$test_arr4 = array();
$test_arr5 = array();
for ($i = 0; $i < $test_arr_size; ++$i)
{
mt_srand();
$hash = md5(mt_rand());
$key = substr($hash, 0, 5).$i;
$test_arr1[$i] = $test_arr2[$i] = $t...
How to subtract 30 days from the current datetime in mysql?
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SELECT * FROM table
WHERE exec_datetime BETWEEN DATE_SUB(NOW(), INTERVAL 30 DAY) AND NOW();
http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_date-add
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