大约有 37,000 项符合查询结果（耗时：0.0130秒） [XML]
Relational table naming convention [closed]
I'm starting a new project and would like to get my table- and column names right from the start. For example I've always used plural in table names but recently learned singular is correct.
...
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...
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.
...
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.
...
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
...
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...
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
...
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...
Django in / not in query
...
table1.objects.exclude(id__in=
table2.objects.filter(your_condition).values_list('id', flat=True))
The exclude function works like the Not operator you where asking for. The attribute flat = True tells to table2 query t...