Alastair, SELECT codecolumn FROM lookuptable + WHERE codecolumn NOT IN + (SELECT codecolumn FROM ForeignKeyTable)
Bill On Mon, 8 Sep 2003 23:02:27 +0100, Alastair Burr wrote: >Hello everyone, >I'm trying to find what codes from a look-up table are not currently in use: >I have a data table that has, amongst other columns, a text column with a >(variable) number of 2 character codes separated by a comma, viz: >aa,ab,ac,ba,bb,bc... >The look-up table has code column with a row for each code and a column with >a description. >I can find which codes are in use easily enough and I thought that the >missing ones could be found by "reversing" the logic but it doesn't work: >Briefly, SELECT... WHERE ... CONTAINS tell me the ones in use but SELECT... >WHERE ... NOT CONTAINS gives me everything. >I can think of a way to do it using a temp table but I wondered if there was >an SQL way to find the unused items? Anybody got any ideas? >Thanks in advance, >Regards, >Alastair. >---------------------------------- >A D B Burr, >St. Albans, UK. >---------------------------------- >[EMAIL PROTECTED] >----------------------------------
