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SQLite UPSERT / UPDATE OR INSERT
... there are two ways to accomplish this, depending on the structure of your table and if you have foreign keys restrictions activated to maintain integrity. I'd like to share this in a clean format to save some time to the people that may be in my situation.
Option 1: You can afford deleting the row...
Cost of len() function
... the most common implementation of the Python language. Here's a link to a table that provides the algorithmic complexity of many different functions in CPython:
TimeComplexity Python Wiki Page
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Code-first vs Model/Database-first [closed]
... unique index on a field or you can not delete hierarchical data in a tree table for this you need a CTE using the context.Table.SqlQuery("select..."). Model/Database first do not have these drawbacks.
– Elisabeth
Jan 31 '13 at 13:51
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What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
... take up different amounts of space and they have different ranges of acceptable values.
Here are the sizes and ranges of values for SQL Server, other RDBMSes have similar documentation:
MySQL
Postgres
Oracle (they just have a NUMBER datatype really)
DB2
Turns out they all use the same specific...
Can you give a Django app a verbose name for use throughout the admin?
...effects what's shown to the user. It's the literal string used to name the table in the database, which requires a schema migration if you're changing an existing model.
– Cerin
Apr 11 '12 at 16:14
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How does @synchronized lock/unlock in Objective-C?
...dn't feel like writing section directives in order build the DWARF3 unwind tables ;-)
– Louis Gerbarg
Aug 1 '09 at 1:33
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Avoid line break between html elements
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nobr is too unreliable, use tables
<table>
<tr>
<td> something </td>
<td> something </td>
</tr>
</table>
It all goes on the same line, everything is level with eachother,...
How can I group by date time column without taking time into consideration
...s fine in oracle
select to_char(columnname, 'DD/MON/yyyy'), count(*) from table_name group by to_char(createddate, 'DD/MON/yyyy');
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delete_all vs destroy_all?
I am looking for the best approach to delete records from a table. For instance, I have a user whose user ID is across many tables. I want to delete this user and every record that has his ID in all tables.
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jQuery remove options from select
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if your dropdown is in a table and you do not have id for it then you can use the following jquery:
var select_object = purchasing_table.rows[row_index].cells[cell_index].childNodes[1];
$(select_object).find('option[value='+site_name+']').remove();
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