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Storing time-series data, relational or non?
... clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a 16 billion row table is instantaneous).
Your table has one serious impediment. Given your description, the actual PK is (Device, Metric, DateTime). (Please don't call it TimeStamp, that mea...
How do I get textual contents from BLOB in Oracle SQL
...HAR2) :
select utl_raw.cast_to_varchar2(dbms_lob.substr(BLOB_FIELD)) from TABLE_WITH_BLOB where ID = '<row id>';
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SQL WHERE.. IN clause multiple columns
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You can make a derived table from the subquery, and join table1 to this derived table:
select * from table1 LEFT JOIN
(
Select CM_PLAN_ID, Individual_ID
From CRM_VCM_CURRENT_LEAD_STATUS
Where Lead_Key = :_Lead_Key
) table2
ON
table1....
Handling an empty UITableView. Print a friendly message
I have a UITableView that in some cases it is legal to be empty. So instead of showing the
background image of the app, I would prefer to print a friendly message in the screen, such as:
...
Getting the name of a child class in the parent class (static context)
...lt;?php
class Base
{
public static function find($id)
{
$table = static::$_table;
$class = static::getClass();
// $data = find_row_data_somehow($table, $id);
$data = array('table' => $table, 'id' => $id);
return new $class($data);
}
pu...
How to scroll to the bottom of a UITableView on the iPhone before the view appears
I have a UITableView that is populated with cells of a variable height. I would like the table to scroll to the bottom when the view is pushed into view.
...
Maximum number of records in a MySQL database table
What is the upper limit of records for MySQL database table. I'm wondering about autoincrement field. What would happen if I add milions of records? How to handle this kind of situations?
Thx!
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Entity Framework - Invalid Column Name '*_ID"
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What I have figured out is when you have an ICollection that references a table and there is no column that it can figure out, it creates one for you to try to make the connection between the tables. This specifically happens with ICollection and has driven me "batty" trying to figure it out.
...
What's the recommended approach to resetting migration history using Django South?
...ion and fake-applies it (since your database already has the corresponding tables). There's no need to drop all the app tables during the process.
Here's what I'm doing on my dev + production server when I need to get rid of all these unneeded dev migrations:
Make sure we have the same DB sche...
Pretty Printing a pandas dataframe
How can I print a pandas dataframe as a nice text-based table, like the following?
9 Answers
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