JOIN
The JOIN command can be used in conjunction with the Omnidex Query Language
QUALIFY command, to allow qualifications across tables. A JOIN statement
follows one or more QUALIFY statements against the from_table, and precedes
one or more QUALIFY statements against the to_table.
Syntax
JOIN [FROM] from_table USING from_join_col TO to_table USING
to_join_col [OWNED BY table_name] [WITH options]
JOIN
Required
[FROM] from_table
Required. The FROM keyword is supported for visual clarity, but is optional.
The from_table parameter is the table in the previous QUALIFY statement.
USING from_join_col
Required - The USING keyword is required. The from_join_col parameter
is the link column in the from_table that will be joined to the link column
in the to_table.
TO to_table
Required. The TO keyword is required. The to_table parameter is the table
that will be joined with the table in the previous QUALIFY statement.
USING to_join_col
Required - The USING keyword is required. The to_join_col parameter is
the link column in the to_table that will be joined to the link column
in the from_table.
OWNED BY table_name
Optional - Lets you specify the table representing the owner of the to_table.
[WITH options]
Optional - Specify options to be used for this command.
Options
Example
The following example qualifies all orders in the Orders table that were
canceled. It then joins the qualified orders to the products table which
are further refined with another qualify. Finally, the qualified product
names are retrieved with a select statement using the odxid WITH option.
>qualify orders where status='cncl'
610 ORDERS (453 CUSTOMERS) records qualify
>join from orders using product_no to products using product_no
99 PRODUCTS records join
>qualify products where product_class='and eqp'
7 PRODUCTS records qualify
>select product_name from products with odxid
PRODUCT_NAME
----------------------------------------
PAPER CUTTER
DIGITAL POSTAL SCALE
ONE STEP CAMERA
OVERHEAD PROJECTOR
RICOH FAX MACHINE
FAX SURGE PROTECTOR
POSTAL SCALE
7 rows returned
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