is this join approach correct?

• sqlguy-736318

  Hall of Fame

  Points: 3859

  More actions

  March 4, 2015 at 9:43 pm

  #301716

  Hello, this is a really basic question but I haven't written SQL joining more than a few tables in a long time. Anyway, please consider the following:

  TableX

  -------

  X1

  X2

  X3

  TableY

  -------

  Y1

  Y2

  Y3

  I need to write a query with the following joins:

  TableX.X1 = TableY.Y1

  TableX.X2 = TableY.Y2

  What is the proper way to do this in SQL? Would it be:

  select x.*

  from TableX x

  join TableY y1 on y1.Y1 = x.X1

  join TableY y2 on y2.Y2 = x.X2

  Is there a more proper way to do this without creating multiple aliases of the same table?

• Eirikur Eiriksson

  SSC Guru

  Points: 182911

  More actions

  March 4, 2015 at 11:30 pm

  #1781824

  Quick suggestion

  😎

  select x.*

  from TableX x

  join TableY y1 on y1.Y1 = x.X1

  and y1.Y2 = x.X2

• sqlguy-736318

  Hall of Fame

  Points: 3859

  More actions

  March 5, 2015 at 12:37 am

  #1781830

  that's it thanks!