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SQL Server: What is the difference between CROSS JOIN and FULL OUTER JOIN?
... cross join produces a cartesian product between the two tables, returning all possible combinations of all rows. It has no on clause because you're just joining everything to everything.
A full outer join is a combination of a left outer and right outer join. It returns all rows in both tables t...
Match whitespace but not newlines
...ghteen horizontal ones which match \h. \s matches twenty-three characters
All whitespace characters are either vertical or horizontal with no overlap, but they are not proper subsets because \h also matches U+00A0 NO-BREAK SPACE, and \v also matches U+0085 NEXT LINE, neither of which are matched by...
How to check if a table exists in a given schema
... (like OIDs) gets lost in translation from the system catalogs - which actually carry all information.
System catalogs
Your question was:
How to check whether a table exists?
SELECT EXISTS (
SELECT FROM pg_catalog.pg_class c
JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHE...
How to remove last n characters from every element in the R vector
... an example of what I would do. I hope it's what you're looking for.
char_array = c("foo_bar","bar_foo","apple","beer")
a = data.frame("data"=char_array,"data2"=1:4)
a$data = substr(a$data,1,nchar(a$data)-3)
a should now contain:
data data2
1 foo_ 1
2 bar_ 2
3 ap 3
4 b 4
...
Hide keyboard when scroll UITableView
...to our UITableViewController class
override func scrollViewDidScroll(_ scrollView: UIScrollView) {
if !tableView.isDecelerating {
view.endEditing(true)
}
}
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Unsubscribe anonymous method in C#
...ered Oct 8 '08 at 15:33
Jacob KrallJacob Krall
24.8k66 gold badges5757 silver badges7373 bronze badges
...
Get generated id after insert
...LiteDatabase().insert("user", "", values) ;
If query exec use select last_insert_rowid()
String sql = "INSERT INTO [user](firstName,lastName) VALUES (\"Ahmad\",\"Aghazadeh\"); select last_insert_rowid()";
DBHelper itemType =new DBHelper();// your dbHelper
c = db.rawQuery(sql, null);
if (c.move...
Best way to store date/time in mongodb
...ISODate()})
> db.test.insert({date: new Date()})
> db.test.find()
{ "_id" : ObjectId("..."), "date" : ISODate("2014-02-10T10:50:42.389Z") }
{ "_id" : ObjectId("..."), "date" : ISODate("2014-02-10T10:50:57.240Z") }
The native type supports a whole range of useful methods out of the box, which...
Can you create nested WITH clauses for Common Table Expressions?
...
Essentially the post means, that you can't do it, but it is not a big problem.
– peterh - Reinstate Monica
May 30 '17 at 14:40
...
NtMapViewOfSection注入 - C/C++ - 清泛网 - 专注C/C++及内核技术
...要特殊的条件比如像管理员权限或者之类的要求
#define _WIN32_WINNT 0x0400
#include <windows.h>
typedef LONG NTSTATUS, *PNTSTATUS;
#define NT_SUCCESS(Status) ((NTSTATUS)(Status) >= 0)
typedef enum _SECTION_INHERIT
{
ViewShare = 1,
ViewUnmap = 2
} SECTION_INHERIT;
...