PadLeft and PadRight C#

C# > String > PadRight & PadLeft

PadRight left aligns the characters in this string, padding on the right with a specified Unicode character.
PadLeft right aligns the characters in this string, padding on the lefy with a specified Unicode character.

Example:

string str = "four";

char pad = '.';
string str2 = str.PadLeft(7, pad); // "...four"
string str3 = str.PadRight(7, pad); //"four..."

StartWith string C#

C# > String > Methods > StartWith

StartWith determines whether the beginning of  a string matches the specified value.

string str = "--comment--";

if (str.StartsWith("--"))
   str = "comment";

String.Join Method C#

C# > String > Join

Join concatenates a specified separator string between each element of a specified String array.

Example

String[] str = { "red","green","blue","yellow" };

String sep = ",";
String result = String.Join(sep, str, 0, 4); // "red,green,blue,yellow"

Rowversion SQL Server

SQL Server > Types > Rowversion

Rowversion in SQL Server is a data type that exposes automatically generated, unique binary numbers within a database. Rowversion is generally used as a mechanism for version-stamping table rows.

Note: Use rowversion instead of timestamp wherever possible

Any update made to one row changes also the rowversion value

Example:

CREATE TABLE #tmp

(
    id       INT PRIMARY KEY,
    name     VARCHAR(20),
    rw       ROWVERSION
)
GO

INSERT #tmp(ID, Name) VALUES (1, 'John')

INSERT #tmp(ID, Name) VALUES (2, 'Dan')
GO

SELECT * FROM #tmp

id name rw
1  John  0x0000000000122432
2  Dan   0x0000000000122433

update

   #tmp
set
   name = 'Bill'
where
   id = 1

SELECT * FROM #tmp

id name rw
1  Bill    0x0000000000122434
2  Dan   0x0000000000122433

drop table #tmp

Substring function C#

C# > String > Substring

Substring function returns a string in a string

Parameters:

         [starting position] [length]

Example:

String myString = "abcdef";

myString = myString.Substring(0, 3); // "abc"

Other examples:

• Remove first character from string

Insert multiple rows WITHOUT repeating INSERT INTO SQL Server

SQL Server > Scripts > Insert multiple rows

create table #user(id int, superiorid int)

insert into #user(id, superiorid) values  (1,null), (2,1) , (3,1)

Get all children of a parent SQL Server

SQL Server > With > Scripts

Get all children of a parent SQL Server

In a hierarchical structure of tables is necessary to traverse the entire structure to find all the children of a parent.

Example:

create table #user(id int, superiorid int)

insert into #user(id, superiorid) values  (1,null), (2,1) , (3,1)

declare @id int

select @id = 1;

with Parent (superiorid,id)

             as
             (
                    select u.superiorid, u.id
                    from #user u
                    where u.ID = @id
                    union all
                    select u.superiorid ,u.ID
                    from #user u
                    inner join Parent p on p.id = u.superiorid
             )     

Select #user.id, #user.superiorid

from #user
inner join Parent p on p.id = #user.id

drop table #user

Result:

id superiorid
1 NULL
2 1
3 1