beautypg.com

Accessing tables with sql commands 9.8 – HEIDENHAIN TNC 320 (77185x-01) ISO programming User Manual

Page 281

background image

Accessing tables with SQL commands

9.8

9

TNC 320 | User's Manual for DIN/ISO Programming | 3/2014

281

Optional:

WHERE selection criteria: A selection criterion

consists of a column name, condition (see

table) and comparative value. Link selection

criteria with logical AND or OR. Program the

comparative value directly or with a Q parameter.

A Q parameter is introduced with a colon and

placed in single quotation marks (see example).
Optional:

ORDER BY column name ASC for ascending
sorting, or

ORDER BY column name DESC for

descending sorting. If you program neither ASC

nor DESC, ascending sorting is executed by

default. The TNC places the selected rows in the

indicated column.
Optional:

FOR UPDATE (keyword): The selected rows

are locked against write-accesses from other

processes.

Condition

Programming

Equal to

= ==

Not equal to

!= <>

Less than

<

Less than or equal to

<=

Greater than

>

Greater than or equal to

>=

Linking multiple conditions:

Logical AND

AND

Logical OR

OR