mysql - Ensure values are not the same in a column -

-

i have table column values should not same. due poor implementation software not check ensure if user enters duplicate or not, therefore entrusted task of writing "simple" sql statement or function @ values in column , ensure not identical. sql executed once month not have efficient.

the column stores int , increment 1 of duplicate values, , keep on doing every time until there no more entries in table have same value column. suggestion should do? not sure start.

thanks insight.

edit: sorry forgot mention values in data not duplicate should stay way. these settings used customers, , should punish them if have duplicate values. if not, should not destroy settings or angry.

it 1 table, contains lot of columns, 1 specific column in particular of type int , never contains nulls, should not have duplicates.

 create table tablename (keycol int identity(1,1), intcol int)  insert tablename values (1), (2), (2), (3), (5), (6), (5), (7), (9)   while exists (     select intcol     tablename     group intcol     having count(*) > 1 ) begin      declare @newvalue int      select @newvalue = min(t1.intcol) + 1     tablename t1     left join tablename t2     on t1.intcol + 1 = t2.intcol     t2.intcol null      update tx     set intcol = @newvalue     tablename tx     intcol =      (select top 1 intcol     tablename t1     group intcol     having count(*) > 1     order intcol)     , keycol = (select min(keycol) tablename t2 t2.intcol = tx.intcol) end  select * tablename order 2

Comments

Post a Comment

Popular posts from this blog

c# - SVN Error : "svnadmin: E205000: Too many arguments" -

-
i trying reposotries using c# code process svncommand = null; var psi = new processstartinfo("svnadmin"); psi.redirectstandardoutput = true; psi.redirectstandarderror = true; psi.useshellexecute = false; psi.arguments= @"dump c:\repositories\myrepo > c:\temp\myrepodumpfile.dump"; using (svncommand = process.start(psi)) { var myoutput = svncommand.standardoutput; var myerror = svncommand.standarderror; debug.write("output :" + environment.newline + environment.newline + myoutput.readtoend() + environment.newline + "error :" + environment.newline + environment.newline + myerror.readtoend()); svncommand.close(); } when use dump command commandline svnadmin dump c:\repositories\myrepo > c:\temp\myrepodumpfile.dump it works fine when try ...
Read more

c# - Copy ObservableCollection to another ObservableCollection -

-
how copy observablecollection item observablecollection without reference of first collection? here observablecollection item value changes affecting both collections. code private observablecollection<ratemodel> _allmetalrate = new observablecollection<ratemodel>(); private observablecollection<ratemodel> _metalrateondate = new observablecollection<ratemodel>(); public observablecollection<ratemodel> allmetalrate { { return this._allmetalrate; } set { this._allmetalrate = value; notifypropertychanged("metalrate"); } } public observablecollection<ratemodel> metalrateondate { { return this._metalrateondate; } set { this._metalrateondate = value; notifypropertychanged("metalrateondate"); } } foreach (var item in metalrateondate) allmetalrate.add(item); what causing , how can solve it? you need clone object referenced item before it's a...
Read more

All overlapping substrings matching a java regex -

-
is there api method returns (possibly overlapping) substrings match regular expression? for example, have text string: string t = 04/31 412-555-1235; , , have pattern: pattern p = new pattern("\\d\\d+"); matches strings of 2 or more characters. the matches are: 04, 31, 412, 555, 1235. how overlapping matches? i want code return: 04, 31, 41, 412, 12, 55, 555, 55, 12, 123, 1235, 23, 235, 35. theoretically should possible -- there obvious o(n^2) algorithm enumerates , checks substrings against pattern. edit rather enumerating substrings, safer use region(int start, int end) method in matcher . checking pattern against separate, extracted substring might change result of match (e.g. if there non-capturing group or word boundary check @ start/end of pattern). edit 2 actually, it's unclear whether region() expect zero-width matches. specification vague, , experiments yield disappointing results. for example: string line = "xx90xx"; strin...
Read more