Обсуждение: postgresql system column errors
Hello Hiroshi, When I try to use the column name xmin in one of my tables I get ERROR: column name "xmin" conflicts with a system column name You seem to have been affected by these errors in the past too. Had you found a solution? Anybody else have any solutions? Cheers, ashish Ashish Mahabal, Caltech Astronomy, Pasadena, CA 91125 http://www.astro.caltech.edu/~aam aam@astro.caltech.edu Colorless green ideas sleep furiously.
Ashish Mahabal wrote: >Hello Hiroshi, > >When I try to use the column name xmin in one of my tables I get >ERROR: column name "xmin" conflicts with a system column name > >You seem to have been affected by these errors in the past too. Had you >found a solution? > >Anybody else have any solutions? > > The only thing you can do is change your column name. The manual tells you about the system columns here: http://www.postgresql.org/docs/7.4/static/ddl-system-columns.html -- Mark Gibson <gibsonm |AT| cromwell |DOT| co |DOT| uk> Web Developer & Database Admin Cromwell Tools Ltd. Leicester, England.
Hello I have got an inhouse application which used to connect to MySQL using their C API, which is now being ported to PostGreSQL :) Is there any reference to PGSQL C API() in one page. I went thru the docs but they are divided into multiple HTMLs which is kinda difficult for me to take a printout. Any pointers.....??? Also in MySQL, the structure of resultset returned by MySQL goes thru lot of changes with version so there is always a possibilty of application crashing if we refer to wrong index.....does postgresql suffer from same problem...i have gone thru the api and having a simple knack of it but not much :) regards karam __________________________________ Do you Yahoo!? Yahoo! Finance: Get your refund fast by filing online. http://taxes.yahoo.com/filing.html
Karam Chand <karam_chand03@yahoo.com> writes: > Is there any reference to PGSQL C API() in one page. You probably want to read the libpq chapter. http://www.postgresql.org/docs/7.4/static/libpq.html The first three or so sections cover everything you really need to know about. regards, tom lane
Thanx Mark. Thats what I ended up doing. But it seems silly that the name space for system columns and user columns are not separate. Its just like saying that you can not have the same column name in 2 different tables. Just like I can say table1.myCol and table2.myCol, there should have been a way to say system.xmin and myTable.xmin, the default being myTable.xmin when I am doing stuff with myTable. Whereever xmin gets used currently, the source could explicitely say system.xmin. Anyway. hope that is done in some future version. Cheers, -ashish On Mon, 16 Feb 2004, Mark Gibson wrote: > Ashish Mahabal wrote: > > >Hello Hiroshi, > > > >When I try to use the column name xmin in one of my tables I get > >ERROR: column name "xmin" conflicts with a system column name > > > >You seem to have been affected by these errors in the past too. Had you > >found a solution? > > > >Anybody else have any solutions? > > > > > > The only thing you can do is change your column name. > > The manual tells you about the system columns here: > http://www.postgresql.org/docs/7.4/static/ddl-system-columns.html > > -- > Mark Gibson <gibsonm |AT| cromwell |DOT| co |DOT| uk> > Web Developer & Database Admin > Cromwell Tools Ltd. > Leicester, England. > Ashish Mahabal, Caltech Astronomy, Pasadena, CA 91125 http://www.astro.caltech.edu/~aam aam@astro.caltech.edu "Alcohol and calculus don't mix. Never drink and derive."
On Tue, Feb 17, 2004 at 11:15:13AM -0800, Ashish Mahabal wrote: > > Thanx Mark. > > Thats what I ended up doing. But it seems silly that the name space for > system columns and user columns are not separate. Its just like saying > that you can not have the same column name in 2 different tables. > > Just like I can say table1.myCol and table2.myCol, there should have been > a way to say system.xmin and myTable.xmin, the default being myTable.xmin > when I am doing stuff with myTable. Whereever xmin gets used currently, > the source could explicitely say system.xmin. Anyway. hope that is done in > some future version. I think you're missing something. Every table has the xmin, xmax, cmin, cmax and sometimes oid columns. They're not only in the system tables. These columns are what makes transactions work and they exist for every record. I hope you're not suggesting a move to myTable.system.xmin ? Pick a table and do: select xmin,xmax,cmin,cmax from <table> What you're asking is to have the same column name twice in a single table, which is obviously silly. -- Martijn van Oosterhout <kleptog@svana.org> http://svana.org/kleptog/ > If the Catholic church can survive the printing press, science fiction > will certainly weather the advent of bookwarez. > http://craphound.com/ebooksneitherenorbooks.txt - Cory Doctorow