Suppose you have a vector layer in your GRASS GIS database and you want to find all duplicate values in one of the columns of the attribute table of that layer?
If you are using SQLite or PostgreSQL as the database back-end (and you should), this is easy using a SQLite statement. Suppose you have the table sp1th and the column value with duplicate values: Continue reading
I wrote before on using concatenate in OpenOffice / LibreOffice and how this alternatively can be done in R using the paste function. You can do the same in SQLite using a query too. Continue reading
I came across this post by underdark about how to select a random sample from a table in PostgreSQL. You can achieve the same (selecting 1000 random features from a table) in SQLite using something like below: Continue reading
The problem with copy data from e.g., an excel or calc sheet into an SQLite database (or any database I reckon) is that the data you copy might include an carriage return. I found this out the hard way after having copied data from a spreadsheet into a attribute table of a GRASS GIS vector layer (which is stored in a SQLite database). Continue reading