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How to pull a random record using Django's ORM?
... solutions with order_by('?')[:N] are extremely slow even for medium-sized tables if you use MySQL (don't know about other databases).
order_by('?')[:N] will be translated to SELECT ... FROM ... WHERE ... ORDER BY RAND() LIMIT N query.
It means that for every row in table the RAND() function will ...
How to get Top 5 records in SqLite?
...
SELECT * FROM Table_Name LIMIT 5;
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Bring element to front using CSS
...28px;
}
.content {
margin-left: auto;
margin-right: auto;
table-layout: fixed;
border-collapse: collapse;
z-index: -1;
position:relative;
}
.td-main {
text-align: center;
padding: 80px 10px 80px 10px;
border: 1px solid #A02422;
background: #ABABA...
Practical uses of different data structures [closed]
...ound the list in a similar question, previously on StackOverflow:
Hash Table - used for fast data lookup - symbol table for compilers,
database indexing, caches,Unique data representation.
Trie - dictionary, such as one found on a mobile telephone for
autocompletion and spell-checking.
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generate model using user:references vs user_id:integer
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Is it possible to generate a model with references of two tables
– praveenkumar
Dec 8 '16 at 6:41
Not...
Dismiss keyboard by touching background of UITableView
I have a UITableView with UITextField s as cells. I would like to dismiss the keyboard when the background of the UITableView is touched. I'm trying to do this by creating a UIButton the size of the UITableView and placing it behind the UITableView . The only problem is the UIButton i...
Error 1046 No database Selected, how to resolve?
...ell MySQL which database to use:
USE database_name;
before you create a table.
In case the database does not exist, you need to create it as:
CREATE DATABASE database_name;
followed by:
USE database_name;
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Received an invalid column length from the bcp client for colid 6
...the data in the excel for its format to be in compliance with the database table schema.
To avoid this, try exceeding the data-length of the string datatype in the database table.
Hope this helps.
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How to keep index when using pandas merge
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Think I've come up with a different solution. I was joining the left table on index value and the right table on a column value based off index of left table. What I did was a normal merge:
First10ReviewsJoined = pd.merge(First10Reviews, df, left_index=True, right_on='Line Number')
Then I r...
Ruby on Rails generates model field:type - what are the options for field:type?
...tetime, :timestamp,
:time, :date, :binary, :boolean, :references
See the table definitions section.
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