Database Looping
This node runs SQL queries in the connected database restricted by the
possible values given by the input table. It establishes and opens a
database access connection from which to read data and restricts
each SQL query so that only rows that match the possible values from
the input table are retrieved.
The place holder in brackets for table name and table column must be
replaced, while the possible value place holder enclosed in hashes must not
be edit and will be resolved during execution.
If the optional input is connected the database connection information is taken from the port, otherwise
you need to specify the connection information in the dialog.
Make sure you have your vendor-specific database driver registered in
the KNIME preference page (section Database Driver). By default, the
sun.jdbc.odbc.JdbcOdbcDriver (Windows and Linux) is only available.
Dialog Options
- Database Driver
-
Enter the database driver here; it is a Java class (including the
package path), for example: sun.jdbc.odbc.JdbcOdbcDriver
Additional driver can be registered via KNIME's preference page
(Database Driver).
- Database Name
-
Enter the database name here, for example
jdbc:odbc:database_name or jdbc:mysql://host:port/database_name
- Workflow Credentials
-
If checked, the credentials (user and password) are used as defined on
the workflow. The credential name links to the specified user and
password. Those can be replaced or edit using the 'Workflow Credentials'
menu available in the workflow context menu.
- User Name
-
Your log-in user name for the database.
- Password
-
Your log-in password for the database. Note, the password is
de- and encrypted before handling it internally.
- TimeZone
-
Select the TimeZone to convert the date, time or timestamp field into. The current implementation can't
represent time zones. In order to support persisting those fields into a database, the time values can be
changed according to the selected time zone, which is used as the offset (including the daylight saving time)
for the original values: No Correction (use UTC) is used for workflows (created before 2.8) and doesn't
apply any correction, Use local TimeZone uses the local time zone offset to correct the date field
before reading or writing, and TimeZone: allows selecting the time zone to covert the date values into.
- SQL Statement
-
Enter the SQL-like query here, for example SELECT * FROM table. The
WHERE statement is automatically adjusted according to the possible
values of the selected column.
- Column selection
-
Select one column whose possible (distinct) values are used to
constrain the SQL WHERE clause.
- Aggregate by row:
-
If this option is selected, the final output table will only contain one
row per value of the aggregated column. All other column values
are aggregated and separated by comma.
- Append grid column:
-
If this option is selected, the grid column from the input table is
appended to the end of the resulting output table which is case of a
more than one value per query, will contain the set of values.
- No. of Values per Query:
-
Specifies the number of elements executed in each SQL query.
Ports
Input Ports
0 |
Data column with possible values used to constrain the database SQL
query
|
1 |
An optional database connection that should be used instead of providing the connection information
in the dialog.
(optional) |
Output Ports
0 |
Table with data read from the database
|
This node is contained in KNIME Base Nodes
provided by KNIME GmbH, Konstanz, Germany.