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HEIDENHAIN TNC 128 (77184x-02) User Manual

Page 228

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Programming: Q Parameters

8.9

Accessing tables with SQL commands

8

228

TNC 128 | User's Manual HEIDENHAIN Conversational Programming | 5/2014

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