> "even numeric data" is imported as text
Column types in Sqlite are not strictly enforced.
If you import data that 'look' numeric from your
text file into a column with a numeric type, the
data will be stored in a numeric format; if a
particular value cannot be converted to a numeric
format, it will be stored as text -- so you may
have '' in a numeric column where you want a null.
See <www.sqlite.org/datatype3.html> for a more
rigorous explanation.
BTW, you shouldn't have to type individual update
statements for each column. Sqlite is usable from
almost all scripting languages. For example, in
tcl if you get the column names into a variable
called columns, you can do something like
load tclsqlite3.so
sqlite dbcmd filename.db
dbcmd eval {begin exclusive}
foreach c $columns {
dbcmd eval {upate table set $c=null where $c=''}
}
dbcmd eval commit
dbcmd close
Regards
