I am trying to get an Oracle join to work as my Sybase join. The Sybase join returns all results and pads with nulls. The Oracle join doesn't seem to function properly and will not pad the results with nulls. This is operating in Powerbuilder 6.5. Syntax for both are below:
//// ORACLE DRAW SELECT FAST.CONNECTION.CONNECT_ID, FAST.CONNECTION.DESCRIPTION, FAST.ACCOUNT_SU.SSO_LOGIN_ID FROM FAST.CONNECTION, FAST.ACCOUNT_SU WHERE ( FAST.account_su.connect_id = FAST.connection.connect_id ) and (( FAST.account_su.sso_login_id = 'rsmyer' )) AND ( FAST.connection.active_ind = 'y' )
SYBASE DRAW SELECT dbo.connection.connect_id, dbo.connection.description, dbo.account.sso_login_id FROM dbo.connection, dbo.account WHERE ( dbo.connection.connect_id *= dbo.account.connect_id ) and (( dbo.account.sso_login_id = 'rsmyer' )) and ( dbo.connection.active_ind = 'y' )
*=" in the Sybase WHERE
clause means that it's a left outer join, which returns all
rows of the
connection table, with nulls in
for unmatched rows.
A left outer join in Oracle actually has similar syntax,
except that it uses the outer join operator "
instead of an asterisk beside the equal sign.
I'll remove the parentheses in your WHERE
clause to make the Oracle outer join operator more noticeable --
SELECT FAST.CONNECTION.CONNECT_ID, FAST.CONNECTION.DESCRIPTION, FAST.ACCOUNT_SU.SSO_LOGIN_ID FROM FAST.CONNECTION, FAST.ACCOUNT_SU WHERE FAST.account_su.connect_id = FAST.connection.connect_id (+) and FAST.account_su.sso_login_id = 'rsmyer' AND FAST.connection.active_ind = 'y'
Place the outer join operator "
behind the columns of the table that will
receive the nulls.
Actually, you should probably be using SQL standard LEFT OUTER JOIN syntax.
SELECT FAST.CONNECTION.CONNECT_ID, FAST.CONNECTION.DESCRIPTION, FAST.ACCOUNT_SU.SSO_LOGIN_ID FROM FAST.CONNECTION LEFT OUTER JOIN FAST.ACCOUNT_SU ON FAST.account_su.connect_id = FAST.connection.connect_id WHERE FAST.account_su.sso_login_id = 'rsmyer' AND FAST.connection.active_ind = 'y'
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This was first published in June 2002