Left Join

[kenwvs]

I have gone through the database normalization process, and rewrote the queries in php to accomodate this, but now, in preparation for the next step, where the data can be retrieved, I need some help in understanding the LEFT JOIN.

I had been advised that in the many=>many format, I should create a third table, but am now wondering if that was ONLY if my host supported INNODB table types.

I have one table called workorder, where the basic information goes, and a second table where the part number and description of the parts required will go.

The WorkOrder table has the following columns - work_id(primary key, auto-increment), work(work order number (in mmhhddss format), name, site, serial, severity, issue and sched(date)

The Parts table has parts_id(primary key, autoincrement), number, description. 

Do I need to add another column to the Parts Table that would have a field that is the same as the workorder table?  Perhaps the workorder # or use the primary key through the use of the mysql_insert_id(). 

Any direction on this would be appreciated.

Ken

[fenway]

You should still have a 3rd table that relates parts to workorders, which simply contains FK to the PK of both of these tables.