or add a user function 'filename' which does the work and select filename(ID)
On Fri, Jan 26, 2018 at 3:26 PM, Richard Damon <[email protected]> wrote: > One question I have, couldn't you just omit the fileName column from the > able, and compute it in the select query that is getting the data? > > On 1/26/18 6:03 PM, Roman Fleysher wrote: > >> My implementation of "for Each row" requires all columns to be >> populated. It is a dumb thing: >> >> forEachRow commandToBeExecuted itsArgumentsWhichReferToColumns >> >> The files are images. Example: >> >> forEachRow addImages outputColumn column1 column2 >> >> ForEachRow will loop over the rows (in parallel batches if it can) and >> apply the command given to it with its arguments. Image processing is then >> a sequence of these "forEach" commands. >> >> >> Roman >> >> On 1/26/2018 5:47 PM, Roman Fleysher wrote: >> >>> I will use this table as a manager. There will be multiple columns >>> holding various file names. The names can be random, but I want humans to >>> be able to easily inspect. After table is filled, an operation "for each >>> row" will get files in some columns and produce files in other columns. >>> This is done outside of SQLite. "For each row" will process several rows in >>> parallel because they are independent. Some operations might fail and will >>> be recored in the proper columns. After all the work is done, the manager >>> table is discarded. >>> >> I'm still not sure I understand, but: while you are building out this >> manager table, can't you leave fileName column blank, and then right before >> processing, run UPDATE A SET fileName='prefix_'||ID; on it? >> -- >> Igor Tandetnik >> > > -- > Richard Damon > > > _______________________________________________ > sqlite-users mailing list > [email protected] > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users > _______________________________________________ sqlite-users mailing list [email protected] http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
