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How can I add comments in MySQL?
...ified with the COMMENT option. The comment is displayed by the SHOW CREATE TABLE and SHOW FULL COLUMNS statements. This option is operational as of MySQL 4.1. (It is allowed but ignored in earlier versions.)"
As an example
--
-- Table structure for table 'accesslog'
--
CREATE TABLE accesslog (
ai...
sqlite 命令行创建一个空库 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
...库的优势，比touch创建一个空文件好。$sqlite3 foo db "create table t(f int); drop table t;"可以通过以下方 SQLite创建一个空白的数据库，具有被识别为有效的SQLite数据库的优势，比touch创建一个空文件好。
$sqlite3 foo.db "create table t(f int); ...
Why is there extra padding at the top of my UITableView with style UITableViewStyleGrouped in iOS7
Starting in iOS7, there is additional space at the top of my UITableView 's which have a style UITableViewStyleGrouped .
...
Difference Between ViewData and TempData?
...ViewData["City"] = "surat";
return View();
}
try1.cshtm
<table>
<tr>
<th>Name</th>
<th>Twitter</th>
<th>Email</th>
<th>City</th>
<th>Mobile</th>
</tr>
<tr>
<td>@ViewData["...
Linq to Sql: Multiple left outer joins
...se id that was passed in
from category
// left join on categories table if exists
in expenseDataContext.CategoryDtos
.Where(c => c.Id == expense.CategoryId)
.DefaultIfEmpty()
// left join on expense type table if exists
from ...
How would one write object-oriented code in C? [closed]
... (commTcp.open)(commTcp, "bigiron.box.com:5000");
Sort of like a manual vtable.
You could even have virtual classes by setting the pointers to NULL -the behaviour would be slightly different to C++ (a core dump at run-time rather than an error at compile time).
Here's a piece of sample code that...
Undo scaffolding in Rails
...e db:rollback before you destroy your scaffold. This will destroy/drop the table if there is no other migration except the scaffold's migration before it.
– Yakob Ubaidi
May 8 '14 at 11:06
...
#1071 - Specified key was too long; max key length is 767 bytes
...
767 bytes is the stated prefix limitation for InnoDB tables in MySQL version 5.6 (and prior versions). It's 1,000 bytes long for MyISAM tables. In MySQL version 5.7 and upwards this limit has been increased to 3072 bytes.
You also have to be aware that if you set an index on a...
Which method performs better: .Any() vs .Count() > 0?
...esh look on the problem.
Testing env:
EF 6.1.3, SQL Server, 300k records
Table model:
class TestTable
{
[Key]
public int Id { get; set; }
public string Name { get; set; }
public string Surname { get; set; }
}
Test code:
class Program
{
static void Main()
{
usi...
Subqueries vs joins
...ed as a join in which case it executes the subquery for each record in the table rather then join the table in the subquery against the table you are querying. Some of the more "enterprisey" database are better at this, but they still miss it sometimes.
...