Remove Trailing Spaces and Update in Columns in SQL Server

Try SELECT LTRIM(RTRIM('Amit Tech Corp '))

LTRIM - removes any leading spaces from left side of string

RTRIM - removes any spaces from right

Ex:

update table set CompanyName = LTRIM(RTRIM(CompanyName))

To just trim trailing spaces you should use

UPDATE
    TableName
SET
    ColumnName = RTRIM(ColumnName)

However, if you want to trim all leading and trailing spaces then use this

UPDATE
    TableName
SET
    ColumnName = LTRIM(RTRIM(ColumnName))

Well here is a nice script to TRIM all varchar columns on a table dynamically:

--Just change table name
declare @MyTable varchar(100)
set @MyTable = 'MyTable'

--temp table to get column names and a row id
select column_name, ROW_NUMBER() OVER(ORDER BY column_name) as id into #tempcols from INFORMATION_SCHEMA.COLUMNS 
WHERE   DATA_TYPE IN ('varchar', 'nvarchar') and TABLE_NAME = @MyTable

declare @tri int
select @tri = count(*) from #tempcols
declare @i int
select @i = 0
declare @trimmer nvarchar(max)
declare @comma varchar(1)
set @comma = ', '

--Build Update query
select @trimmer = 'UPDATE [dbo].[' + @MyTable + '] SET '

WHILE @i <= @tri 
BEGIN

    IF (@i = @tri)
        BEGIN
        set @comma = ''
        END
    SELECT  @trimmer = @trimmer + CHAR(10)+ '[' + COLUMN_NAME + '] = LTRIM(RTRIM([' + COLUMN_NAME + ']))'+@comma
    FROM    #tempcols
    where id = @i

    select @i = @i+1
END

--execute the entire query
EXEC sp_executesql @trimmer

drop table #tempcols