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LEFT OUTER JOINWhat is a left outer join?
If you don't know what a LEFT OUTER JOIN does in SQL, look into it in the docs. This will eliminate the need to perform many queries outside of SQL. It performs a "non-restrictive" join across multiple tables. In other words, if you try to join a field with a field in another table, if there is no matching entry in another table, the entire row is not disgarded (as with a regular JOIN) but instead NULLs are returned for these columns. To use an example, say for every Company in table C there can be a State in table S which can be linked to the Company in C. However, a State may not be defined for every Company. If you wanted a join which returned all companies and their associated state (NULL if it was not defined) a LEFT OUTER JOIN is the SELECT query for you. Using a regular JOIN would have omitted any Companies for which a State was not defined in this foreign table. Thank you for that insighful explanition.
-- Show quoteArnie Rowland "To be successful, your heart must accompany your knowledge." <intracta***@gmail.com> wrote in message news:1152982637.617901.319220@s13g2000cwa.googlegroups.com... > What is a left outer join? > > If you don't know what a LEFT OUTER JOIN does in SQL, look into it in > the docs. This will eliminate the need to perform many queries outside > of SQL. It performs a "non-restrictive" join across multiple tables. In > other words, if you try to join a field with a field in another table, > if there is no matching entry in another table, the entire row is not > disgarded (as with a regular JOIN) but instead NULLs are returned for > these columns. To use an example, say for every Company in table C > there can be a State in table S which can be linked to the Company in > C. However, a State may not be defined for every Company. If you wanted > a join which returned all companies and their associated state (NULL if > it was not defined) a LEFT OUTER JOIN is the SELECT query for you. > Using a regular JOIN would have omitted any Companies for which a State > was not defined in this foreign table. > Whiskey Tango Foxtrot?
intracta***@gmail.com wrote: Show quote > What is a left outer join? > > If you don't know what a LEFT OUTER JOIN does in SQL, look into it in > the docs. This will eliminate the need to perform many queries outside > of SQL. It performs a "non-restrictive" join across multiple tables. In > other words, if you try to join a field with a field in another table, > if there is no matching entry in another table, the entire row is not > disgarded (as with a regular JOIN) but instead NULLs are returned for > these columns. To use an example, say for every Company in table C > there can be a State in table S which can be linked to the Company in > C. However, a State may not be defined for every Company. If you wanted > a join which returned all companies and their associated state (NULL if > it was not defined) a LEFT OUTER JOIN is the SELECT query for you. > Using a regular JOIN would have omitted any Companies for which a State > was not defined in this foreign table. Why ALL the sarcasm and nasties?Whatever happened to the benefit
of the doubt?Perhaps the op had an epiphany.In which case you just hissed on his parade.Of all places why send the message 'Curb Your Enthusiasm'. You really want to play redneck forum? At least I'm not pushing a product every other post :)
Steve Dassin wrote: Show quote > Why ALL the sarcasm and nasties?Whatever happened to the benefit > of the doubt?Perhaps the op had an epiphany.In which case you just hissed > on his parade.Of all places why send the message 'Curb Your Enthusiasm'. > You really want to play redneck forum? Touché!
-- Show quoteArnie Rowland "To be successful, your heart must accompany your knowledge." "Stu" <stuart.ainswo***@gmail.com> wrote in message news:1153054249.056545.130810@35g2000cwc.googlegroups.com... > At least I'm not pushing a product every other post :) > > Steve Dassin wrote: >> Why ALL the sarcasm and nasties?Whatever happened to the benefit >> of the doubt?Perhaps the op had an epiphany.In which case you just hissed >> on his parade.Of all places why send the message 'Curb Your Enthusiasm'. >> You really want to play redneck forum? > Have I been ex-communicated by MS (Mafia of Sql) ? :(
Show quote "Arnie Rowland" <ar***@1568.com> wrote in message news:%23sVHJqNqGHA.4032@TK2MSFTNGP03.phx.gbl... > Touché! > > -- > Arnie Rowland > "To be successful, your heart must accompany your knowledge." > > > > "Stu" <stuart.ainswo***@gmail.com> wrote in message > news:1153054249.056545.130810@35g2000cwc.googlegroups.com... >> At least I'm not pushing a product every other post :) Not by me Steve. I do note, however, that most of your posts are only to OPs
that may be served by your product. And hey, we all have to make a living. I have no value judgement about it, just observation. -- Show quoteArnie Rowland "To be successful, your heart must accompany your knowledge." "Steve Dassin" <steve@nospamrac4sql.net> wrote in message news:usaffvQqGHA.4100@TK2MSFTNGP03.phx.gbl... > Have I been ex-communicated by MS (Mafia of Sql) ? :( > > "Arnie Rowland" <ar***@1568.com> wrote in message > news:%23sVHJqNqGHA.4032@TK2MSFTNGP03.phx.gbl... >> Touché! >> >> -- >> Arnie Rowland >> "To be successful, your heart must accompany your knowledge." >> >> >> >> "Stu" <stuart.ainswo***@gmail.com> wrote in message >> news:1153054249.056545.130810@35g2000cwc.googlegroups.com... >>> At least I'm not pushing a product every other post :) > > Oh I don't make a 'living' with RAC, I sell insurance for that.
As for other posts, I'm trying to get the hang of programming sql :) Show quote "Arnie Rowland" <ar***@1568.com> wrote in message news:e4lTWCUqGHA.516@TK2MSFTNGP05.phx.gbl... > Not by me Steve. I do note, however, that most of your posts are only to OPs > that may be served by your product. > > And hey, we all have to make a living. I have no value judgement about it, > just observation. > > -- > Arnie Rowland > "To be successful, your heart must accompany your knowledge." > > > > "Steve Dassin" <steve@nospamrac4sql.net> wrote in message > news:usaffvQqGHA.4100@TK2MSFTNGP03.phx.gbl... > > Have I been ex-communicated by MS (Mafia of Sql) ? :( > > > > "Arnie Rowland" <ar***@1568.com> wrote in message > > news:%23sVHJqNqGHA.4032@TK2MSFTNGP03.phx.gbl... > >> Touché! > >> > >> -- > >> Arnie Rowland > >> "To be successful, your heart must accompany your knowledge." > >> > >> > >> > >> "Stu" <stuart.ainswo***@gmail.com> wrote in message > >> news:1153054249.056545.130810@35g2000cwc.googlegroups.com... > >>> At least I'm not pushing a product every other post :) > > > > > > How about lunch someday soon?
-- Show quoteArnie Rowland "To be successful, your heart must accompany your knowledge." "Steve Dassin" <rac4sqlnospam@net> wrote in message news:%23boaFfiqGHA.5012@TK2MSFTNGP03.phx.gbl... > Oh I don't make a 'living' with RAC, I sell insurance for that. > As for other posts, I'm trying to get the hang of programming sql :) > > "Arnie Rowland" <ar***@1568.com> wrote in message > news:e4lTWCUqGHA.516@TK2MSFTNGP05.phx.gbl... >> Not by me Steve. I do note, however, that most of your posts are only to > OPs >> that may be served by your product. >> >> And hey, we all have to make a living. I have no value judgement about >> it, >> just observation. >> >> -- >> Arnie Rowland >> "To be successful, your heart must accompany your knowledge." >> >> >> >> "Steve Dassin" <steve@nospamrac4sql.net> wrote in message >> news:usaffvQqGHA.4100@TK2MSFTNGP03.phx.gbl... >> > Have I been ex-communicated by MS (Mafia of Sql) ? :( >> > >> > "Arnie Rowland" <ar***@1568.com> wrote in message >> > news:%23sVHJqNqGHA.4032@TK2MSFTNGP03.phx.gbl... >> >> Touché! >> >> >> >> -- >> >> Arnie Rowland >> >> "To be successful, your heart must accompany your knowledge." >> >> >> >> >> >> >> >> "Stu" <stuart.ainswo***@gmail.com> wrote in message >> >> news:1153054249.056545.130810@35g2000cwc.googlegroups.com... >> >>> At least I'm not pushing a product every other post :) >> > >> > >> >> > > "Arnie Rowland" <ar***@1568.com> wrote in message Lunch, there's a subject I know something about!news:%23M5QFmiqGHA.4992@TK2MSFTNGP05.phx.gbl... > How about lunch someday soon? Although your timeline leaves something to be desired:(:) Well you seem to have a bit of sport in ya which is not a commodity around here. Be nice to newbies and don't beat up the mvps to much:) intracta***@gmail.com wrote:
Show quote > What is a left outer join? Whew, finally I can sleep. I've stayed up late every night this week > > If you don't know what a LEFT OUTER JOIN does in SQL, look into it in > the docs. This will eliminate the need to perform many queries outside > of SQL. It performs a "non-restrictive" join across multiple tables. In > other words, if you try to join a field with a field in another table, > if there is no matching entry in another table, the entire row is not > disgarded (as with a regular JOIN) but instead NULLs are returned for > these columns. To use an example, say for every Company in table C > there can be a State in table S which can be linked to the Company in > C. However, a State may not be defined for every Company. If you wanted > a join which returned all companies and their associated state (NULL if > it was not defined) a LEFT OUTER JOIN is the SELECT query for you. > Using a regular JOIN would have omitted any Companies for which a State > was not defined in this foreign table. > pondering this very question...  |
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