Joiner
This node joins two tables in a database-like way. The join is based
on the joining columns of both tables.
Dialog Options
Joiner settings
- Join mode
-
If a row from the top table cannot be joined with a row from the bottom table (and vice versa) there are
several options of handling this situation. After an
Inner Join
only matching rows will show up in the output table. A
Left Outer Join
will fill up the columns that come from the bottom table with missing values if no matching row exists in
the bottom table. Likewise, a
Right Outer Join
will fill up the columns from the top table with missing values if no matching row in the top table
exists. A
Full Outer Join
will fill up columns from both the top and bottom table with missing values if a row cannot be joined.
- Joining columns
-
Select the columns from the top input ('left' table) and the bottom input
('right' table) that should be used for joining. You may selected a real
column or the table's row ID here. You must make sure, that the type
of selected columns matches. The row IDs are interpreted as
StringCells.
Match all of the following:
A row of the top input table and a row of the bottom input table
match if they match in all specified column pairs.
Match any of the following:
A row of the top input table and a row of the bottom input table
match if they match in at least one specified column pairs.
- Performance Tuning
-
Maximum number of open files: The maximum number of opened
temporary files. Increase it for better performance.
Enable hiliting: Select, if hiliting is enabled between
input and output data. Disable, for reducing memory consumption.
- Row ID separator in joined table
-
The row IDs of the joined table are a concatenation of the row ID
of the top input table, this separator and the row ID of the bottom
input table.
Column selection
- Column Selection (Top Input ('left' table) and Bottom Input ('right' table))
-
Exclude: This list contains the column names of the input table that are
excluded.
Select: Use these buttons to move columns between the Include and Exclude
list.
Include: This list contains the column names that are included.
Search: Use one of these fields to search either within the Include
or Exclude list for certain column names or name substrings.
Repeated clicking of the search button marks the next column that
matches the search text. The check box 'Select all search hits' causes
all matching columns to be selected making them movable between
the two lists.
Always include all columns: If set, all columns are moved to
the include list and if input changes all new columns will be in the
include list, too.
- Duplicate column handling
-
The option allows you to change the behaviour if the include
lists of both input tables contain columns with the same name.
Filter duplicates: Only the columns from the top input table
will show up in the output table.
Don't execute: Don't allow to execute this node if there are
duplicate column names in the include lists.
Append suffix: Append a suffix to the duplicate column names
from the bottom input table so that they also show up in the output
table.
- Joining columns handling
-
The option allows filtering the top ('left' table) or bottom ('right' table) joining columns, i.e. the
joining columns defined in the Joiner Settings tab will not show up in the output table.
Ports
Input Ports
0 |
Table contributing to the left part of the output table |
1 |
Table contributing to the right part of the output table |
This node is contained in KNIME Base Nodes
provided by KNIME GmbH, Konstanz, Germany.