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Select n random rows from SQL Server table
I've got a SQL Server table with about 50,000 rows in it. I want to select about 5,000 of those rows at random. I've thought of a complicated way, creating a temp table with a "random number" column, copying my table into that, looping through the temp table and updating each row with RAND() , and ...
Table header to stay fixed at the top when user scrolls it out of view with jQuery
I am trying to design an HTML table where the header will stay at the top of the page when AND ONLY when the user scrolls it out of view. For example, the table may be 500 pixels down from the page, how do I make it so that if the user scrolls the header out of view (browser detects its no longer i...
mysql - how many columns is too many?
I'm setting up a table that might have upwards of 70 columns. I'm now thinking about splitting it up as some of the data in the columns won't be needed every time the table is accessed. Then again, if I do this I'm left with having to use joins.
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Fastest way to replace NAs in a large data.table
I have a large data.table , with many missing values scattered throughout its ~200k rows and 200 columns. I would like to re code those NA values to zeros as efficiently as possible.
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Jquery insert new row into table at a certain index
I know how to append or prepend a new row into a table using jquery:
9 Answers
9
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Convert generic List/Enumerable to DataTable?
...te using FastMember from NuGet:
IEnumerable<SomeType> data = ...
DataTable table = new DataTable();
using(var reader = ObjectReader.Create(data)) {
table.Load(reader);
}
This uses FastMember's meta-programming API for maximum performance. If you want to restrict it to particular members (...
Advantages of Binary Search Trees over Hash Tables
What are the advantages of binary search trees over hash tables?
18 Answers
18
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MySQL: Insert record if not exists in table
...er way to do it, but you can actually do what you were attempting:
CREATE TABLE `table_listnames` (
`id` int(11) NOT NULL auto_increment,
`name` varchar(255) NOT NULL,
`address` varchar(255) NOT NULL,
`tele` varchar(255) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB;
Insert a record:
I...
Implementing Comments and Likes in database
...
The most extensible solution is to have just one "base" table (connected to "likes", tags and comments), and "inherit" all other tables from it. Adding a new kind of entity involves just adding a new "inherited" table - it then automatically plugs into the whole like/tag/comment m...
How to set tbody height with overflow scroll
...u want tbody to show a scroll , turn it into a block.
To keep behavior of table , turn tr into table.
to spray evenly the cells , use table-layout:fixed;
DEMO
CSS for your HTML test :
table ,tr td{
border:1px solid red
}
tbody {
display:block;
height:50px;
overflow:auto;
}
t...