Updating databases
Quick reference
To update an old database for use with a newer version of Quanvert Text, go to the database directory and type:
qvupdate
Windows-based Quanvert runs qvupdate itself when necessary.
Note The qvupdate program is distributed as part of Quanvert Text and Windows-based Quanvert.
More information
As Quanvert develops, the internal structures of some files change and new files become required in order for Quanvert to run. In most cases you can update a database just by reflipping it, but where this is not practical you can run the qvupdate program instead. Windows-based Quanvert runs qvupdate automatically when it is needed.
The notes below list the things that qvupdate does:
▪If the titles.inf file does not exist, qvupdate creates it by running qvtitles (wqvtitle.exe in Windows-based Quanvert). The titles.inf file contains a title for each axis, numeric, alpha and bit variable.
Version 8.4a and later of flip create this file automatically.
▪If file wtnames does not exist for a weighted database, qvupdate creates a file called wtnames, which gives each weighting matrix a name of the form Weight_n where n is a number.
▪What qvupdate does next depends on whether the file descrips.inf already exists or not:
If descrips.inf does not exist, qvupdate uses titles.inf and wtnames and other information to create a descrips.inf file.
If descrips.inf does exist, qvupdate updates it but ignores information in the titles.inf and wtnames files.
▪If any of the following are out of date, qvupdate runs the program qvaddmar (wqvadmar.exe in Windows-based Quanvert) to make them up to date:
▪If marginal values have not been copied from *.fli to *.ax, they are copied. Windows-based Quanvert looks for marginals in the .ax files but Quanvert Text does not. Version 8.2 and later of flip do this automatically.
▪If flags indicating which axes are multicoded have not been set in the axes.inf file, they are set. Only Windows-based Quanvert uses these. Version 12.3 and later of flip do this automatically.
▪If flags indicating which multicoded axes are single coded for the purposes of exporting to SAS, SPSS or ASCII format have not been set in the axes.inf file, they are set. Only Windows-based Quanvert uses these.
▪If any of the following are out of date, qvupdate runs the program wtincs (wwtincs.exe in Windows-based Quanvert) to make them up to date:
▪For each weighting matrix, a numeric variable is created using the names in the wtnames file, which by default are in the form Weight_n. Versions 12.3 and later of flip do this automatically.
▪For each valid pair of levels, qvupdate creates a file called lv_m_n (where m is the upper level and n is the lower level) containing, for each case at the upper level, the number of lower level cases inside it. For example, if level 1 is households and level 2 is people, lv_1_2 is created at the household level and contains a count of people in each household. A pair of levels is valid if they are ancestor-and-descendent, but not if they are siblings, uncles, and so on.
Flip does not create these files.
▪In ordinary, non-levels databases qvupdate creates a variable called uniq_id containing a unique number for each respondent. These numbers start at 1 for the first respondent and are sequential throughout the rest of the database. In levels databases, qvupdate creates a separate file for each level. Each file is named with its level name and contains a number for each respondent or case at that level. Numbering is sequential from 1 in each file.
Flip does not create these variables.
Note Users of Quanvert Text databases may also find these files useful for checking individual respondent records or for filtering.
See also