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django : using select_related and get_object_or_404 together
Is there any way of using get_object_or_404 and select_related together or any other way to achieve the result of using these two together(except from putting it in try/except)??
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How do I get the MAX row with a GROUP BY in LINQ query?
...t by t.SerialNumber
into g
select new
{
SerialNumber = g.Key,
uid = (from t2 in g select t2.uid).Max()
};
}
...
How to check if a column exists in a SQL Server table?
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SQL Server 2005 onwards:
IF EXISTS(SELECT 1 FROM sys.columns
WHERE Name = N'columnName'
AND Object_ID = Object_ID(N'schemaName.tableName'))
BEGIN
-- Column Exists
END
Martin Smith's version is shorter:
IF COL_LENGTH('schemaName.tabl...
How to convert all tables from MyISAM into InnoDB?
...database here first
//
// Actual code starts here
$sql = "SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'your_database_name'
AND ENGINE = 'MyISAM'";
$rs = mysql_query($sql);
while($row = mysql_fetch_array($rs))
{
$tbl = ...
Selecting the last value of a column
...
Another good resource is the selected answer at productforums.google.com/forum/#!topic/docs/p3t3feg7Jic which shows how to get the first, last, or nth row in a FILTER()ed range, similar to @Geta's answer.
– Aaron Blenkush
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How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
... 0.0 NaN 0.0
3 0.0 1.0 2.0 3.0
4 NaN 0.0 NaN NaN
If you want to select the rows that have two or more columns with null value, you run the following:
>>> qty_of_nuls = 2
>>> df.iloc[df[(df.isnull().sum(axis=1) >=qty_of_nuls)].index]
0 1 2 3
1 0.0 NaN 0...
mysql -> insert into tbl (select from another table) and some default values [duplicate]
As the title says, I am trying to insert into one table selecting values from another table and some default values.
5 Ans...
jquery input select all on focus
I'm using this code to try and select all of the text in the field when a user focuses on the field. What happens is, it selects all for a second, then its unselected and the typing cursor is left where I clicked...
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T-SQL: Deleting all duplicate rows but keeping one [duplicate]
... I do not care about that. I still need to keep one of these rows however. SELECT DISTINCT won't work because it operates on all columns and I need to suppress duplicates based on the key columns.
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Converting Select results into Insert script - SQL Server [closed]
...asier than installing plugins or external tools in some situations:
Do a select [whatever you need]INTO temp.table_namefrom [... etc ...].
Right-click on the database in the Object Explorer => Tasks => Generate Scripts
Select temp.table_name in the "Choose Objects" screen, click Next.
In the...