ananth@mandrill.CWRU.Edu (ananth srinivasan) (04/12/88)
I have a problem with dBaseIII+ syntax and would appreciate any help. I have two relations with join-able attributes (say ID) and I need to find out those ID's that exist in one and don't exist in the other. In SQL I can use the NOT EXISTS syntax; in QUEL I can use the ANY...=0 syntax; and in Rbase V I can use the SUBTRACT operator (which really makes the most sense). My question is what is the appropriate syntax in dBase?
wew@naucse.UUCP (Bill Wilson) (04/19/88)
In article <2413@mandrill.CWRU.Edu>, ananth@mandrill.CWRU.Edu (ananth srinivasan) writes: > I have a problem with dBaseIII+ syntax and would appreciate any help. > I have two relations with join-able attributes (say ID) and I need > to find out those ID's that exist in one and don't exist in the other. > In SQL I can use the NOT EXISTS syntax; in QUEL I can use the > ANY...=0 syntax; and in Rbase V I can use the SUBTRACT operator > (which really makes the most sense). My question is what is the > appropriate syntax in dBase? After setting your relations up, try the following: select 1 accept 'Enter ID: ' to ID seek ID select 2 if eof() ? 'That ID is not in the second database.' endif This assumes that ID is a character field and that the files are indexed on ID for both. If you hve any other problems feel free to contact me. I have some friends that do custom dBASE work if you have any good sized projects. Bill Wilson 602-523-6461 Bitnet: ucc2wew@nauvm
steve@violet.berkeley.edu (Steve Goldfield) (04/19/88)
In article <2413@mandrill.CWRU.Edu> ananth@mandrill.CWRU.Edu (ananth srinivasan) writes:
#>I have a problem with dBaseIII+ syntax and would appreciate any help.
#>I have two relations with join-able attributes (say ID) and I need
#>to find out those ID's that exist in one and don't exist in the other.
#>In SQL I can use the NOT EXISTS syntax; in QUEL I can use the
#>ANY...=0 syntax; and in Rbase V I can use the SUBTRACT operator
#>(which really makes the most sense). My question is what is the
#>appropriate syntax in dBase?
Unless you have a feature I don't know about with the plus,
all you can do in dBase is to index both files and then loop
through each doing a find on the other.steve@violet.berkeley.edu (Steve Goldfield) (04/19/88)
In article <640@naucse.UUCP> wew@naucse.UUCP (Bill Wilson) writes:
#
#After setting your relations up, try the following:
#
#select 1
#accept 'Enter ID: ' to ID
#seek ID
#select 2
#if eof()
# ? 'That ID is not in the second database.'
#endif
#
#This assumes that ID is a character field and that the files
#are indexed on ID for both.
I suspect that the above isn't what the questioner wanted.
Instead try (I'm assuming that dBASE III+ syntax is
similar to that of McMax).
select 1
Do while .not. eof()
store id to idvar
select 2
find &idvar
if .not. found()
set print on
? idvar,' not in second database'
set print off
endif
select 1
skip
enddo
select 2
do while .not. eof()
store id to idvar
select 1
find &idvar
if .not. found()
set print on
? idvar, ' not in first database'
set print off
endif
select 2
skip
enddo
set print on
eject
set print offambrose@iris.ucdavis.edu (Paul Ambrose) (04/20/88)
In article <640@naucse.UUCP> wew@naucse.UUCP (Bill Wilson) writes: >In article <2413@mandrill.CWRU.Edu>, ananth@mandrill.CWRU.Edu (ananth srinivasan) writes: >> I have a problem with dBaseIII+ syntax and would appreciate any help. >> I have two relations with join-able attributes (say ID) and I need >> to find out those ID's that exist in one and don't exist in the other. >> In SQL I can use the NOT EXISTS syntax; in QUEL I can use the >> ANY...=0 syntax; and in Rbase V I can use the SUBTRACT operator >> (which really makes the most sense). My question is what is the >> appropriate syntax in dBase? My DB3 is rusty, but I know the following works: Given two tables, A and B, you can determine records in A that do not have corresponding IDs in B by: select 1 use B index on ID field select 2 use A *(Index A here if desired) set relation on ID into B list field_list_of_A for id <> B->id The *for* condition (<>) will be true for all those records in A that do not have a correspponding ID's in B. Obviously, reversing the A's and B's will give the opposite, that is, all records in B and no corresponding IDs in A. In both cases, the statement: list field_list_of_A for id = B->id will give those records with IDs in both tables. Of course, you can use count, report, label, etc., instead of the list statement.
dgp@ncsc1.ATT.COM (Dennis Pelton x8876) (05/11/89)
I am helping a friend on a small SCO-Xenix system. She wants a beginner's book on Foxbase+ or dBase III+. I only do mainframes and don't have any idea what to recommend. Could anyone, in good conscience, recommend such a book? Please email, I will post a summary. Dennis Pelton att.com.UUCP!ncsc5!dgp