Why not encode (speak / say) what you want to do directly, rather than prayerfully relying on implementation details --
select col1, col2 from mytable order by cast(body_size as float); --- The fact that there's a Highway to Hell but only a Stairway to Heaven says a lot about anticipated traffic volume. >-----Original Message----- >From: sqlite-users [mailto:sqlite-users- >boun...@mailinglists.sqlite.org] On Behalf Of Tim Streater >Sent: Thursday, 17 May, 2018 15:42 >To: SQLite mailing list >Subject: [sqlite] Function to use to convert a text float to a float >for use in ORDER BY > >My db has a table with a column defined thus: > > body_size text default '0.0' > >whose purpose is to hold the size of the item that the row >represents. All rows contain a value but as a string to one decimal >place, not a number. So the column contains strings such as '0.0', >'3.7', '22.9', etc. All are positive. > >Now I want to use the body_size in an ORDER BY so I'll need SQLite to >convert the values to a float. What will be the best function to use? >I'd thought of this: > > select col1, col2 from mytable order by round(body_size,1) > >however the doc doesn't specify whether round accepts a non-numeric >argument. Perhaps: > > select col1, col2 from mytable order by abs(body_size) > >would be better, but I wonder which is fastest (although speed may >not matter too much, the typical select shouldn't return more than >few thousand rows). > > >-- >Cheers -- Tim >_______________________________________________ >sqlite-users mailing list >sqlite-users@mailinglists.sqlite.org >http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
