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Programming Q Parameters | Accessing tables with SQL commands
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HEIDENHAIN | TNC 640 | Conversational Programming User's Manual | 10/2017
Example: table name defined with path and file name
. . .
20 SQL Q5 "SELECT Meas_No,Meas_X,Meas_Y, Meas_Z FROM ’V:
\table\Tab_Example’ WHERE Meas_No<20"
Parameter No. for result
(return value for the
control):
0
successful read operation
1
faulty read operation
Database: SQL command text
: programming
SQL instruction
SELECT
with the table column(s) to be
transferred (separate multiple columns with
,
)
FROM
with a table’s synonym or path (place
the path in single quotation marks)
WHERE
(optional) with column names,
condition, and comparison value (Q
parameters after
:
in single quotation marks)
ORDER BY
(optional) with column names and
type of ordering (
ASC
for ascending,
DESC
for
descending order)
FOR UPDATE
(optional) to lock write access to
the selected row for other processes
Conditions for
WHERE
entries
Condition Programming
Equals = ==
Not equal to != <>
Less than <
Less than or equal to <=
Greater than >
Greater than or equal to >=
empty IS NULL
Not empty IS NOT NULL
Linking multiple conditions:
Logical AND AND
Logical OR OR