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How to list records with date from the last 10 days?
...hy don't you just try it?
The standard ANSI SQL format would be:
SELECT Table.date
FROM Table
WHERE date > current_date - interval '10' day;
I prefer that format as it makes things easier to read (but it is the same as current_date - 10).
...
Backwards migration with Django South
...ur_app, South runs all new migrations, in order. (It looks at the database tables to decide which ones are 'new').
However, you can also specify any migration by number, and South will migrate your database, either forward or backward, to take it to that point. So, with the example files above, if ...
How do Trigonometric functions work?
...
Note that the table of values used by CORDIC must be pre-calculated. So, Taylor might still be used at "compile time".
– Rhubbarb
May 22 '13 at 21:38
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Add a column to a table, if it does not already exist
I want to write a query for MS SQL Server that adds a column into a table. But I don't want any error display, when I run/execute the following query.
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How to check Oracle database for long running queries
... object_name
/
This is a good one for finding long operations (e.g. full table scans). If it is because of lots of short operations, nothing will show up.
COLUMN percent FORMAT 999.99
SELECT sid, to_char(start_time,'hh24:mi:ss') stime,
message,( sofar/totalwork)* 100 percent
FROM v$session_l...
cartesian product in pandas
... 6
See here for the documentation: http://pandas.pydata.org/pandas-docs/stable/merging.html#brief-primer-on-merge-methods-relational-algebra
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f...
When does a process get SIGABRT (signal 6)?
...sses inside pointer to itself.
the A ctor calls pure virtual method before table was filled with valid pointer,
because d is not constructed yet.
#include<iostream>
using namespace std;
class A {
public:
A(A *pa){pa->f();}
virtual void f()=0;
};
class D : public A {
public:
D():A(this)...
How do I (or can I) SELECT DISTINCT on multiple columns?
I need to retrieve all rows from a table where 2 columns combined are all different. So I want all the sales that do not have any other sales that happened on the same day for the same price. The sales that are unique based on day and price will get updated to an active status.
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What is sharding and why is it important?
... Horizontal partitioning is a design principle whereby rows of a database table are held separately, rather than splitting by columns (as for normalization). Each partition forms part of a shard, which may in turn be located on a separate database server or physical location. The advantage is the n...
Storing images in SQL Server?
...pending on your use
If you decide to put your pictures into a SQL Server table, I would strongly recommend using a separate table for storing those pictures - do not store the employee photo in the employee table - keep them in a separate table. That way, the Employee table can stay lean and mean ...