Problem Concatenation

besco · Post by **besco** » Fri Jun 11, 2004 6:58 am

I want to concatene 2 Sequential File in one Sequential File. Is it possible ?
When I test it, I have just DATA of one sequential file but not of the two. The structure is always the same (just one columns).

chulett · Post by **chulett** » Fri Jun 11, 2004 7:04 am

How are you doing the 'concatenation'? Hopefully, not with two output links both trying to write to the same sequential file at the same time.

That simply cannot be done.

Write to two different sequential files and then (in the After Job arena) either concatenate one onto the end of the other or the two together into a new file. A simple shell script can do this or you can issue the commands directly using ExecSH after job.

denzilsyb · Post by **denzilsyb** » Fri Jun 11, 2004 7:05 am

In the sequential file stage, use the 'Append' option, instead of the overwrite option.

chulett · Post by **chulett** » Fri Jun 11, 2004 7:11 am

denzilsyb wrote:In the sequential file stage, use the 'Append' option, instead of the overwrite option.

Only if two jobs or steps are involved!

Yes, a second file can be appended to the end of an existing file, but people that haven't faced this issue before shouldn't think they can do this all at once.

besco · Post by **besco** » Fri Jun 11, 2004 7:32 am

About this, i have my first row in differents files which is the name of columns. When I concatene all this files with a unique columns, I don't know how to keep only one time the first row in the final file. I obtain several times the row with column names. My idea is to extract in a file only the first row, can i do that ?

kab123 · Post by **kab123** » Fri Jun 11, 2004 7:34 am

In The Target Seq file, in the inputs tab, default is set to 'over write existing file',you have to select for second seq file as append existing file.
I think this will do.

besco · Post by **besco** » Fri Jun 11, 2004 7:39 am

Chullet has rigth. I had already check the append option but it doesn't work.

chulett · Post by **chulett** » Fri Jun 11, 2004 9:06 am

It works just fine... as long as it is the only process writing to the file.

If you are building these two outputs simultaneously, then you must write them to two distinct filenames. After the job completes you can combine them however you please.

ray.wurlod · Post by **ray.wurlod** » Fri Jun 11, 2004 7:14 pm

Depending on what you want to do, it may be sufficient to write to two files, then use the cat command to append the second to the first.

On the other hand, if you want to append columns from one file to each row in the first file, then what you need is the Merge stage. The Merge stage performs various kinds of join between text files.

besco · Post by **besco** » Mon Jun 14, 2004 1:44 am

It works now. I just have two Stage "Sequential File", with a bond between the two. Thanks very much for your answers !!