Remove Join (Data Management)

Summary

Removes a join from a feature layer or table view.

Usage

• The Join parameter is the name of the table that was joined to the input layer or table view.

  • If the join table was a dBASE file named MyTable.dbf, the join name would be "MyTable"; so to remove it, specify "MyTable".
  • If the join table was an INFO or Geodatabase Table named MyTable2, the Join Name would be "MyTable2"; so to remove it, specify "MyTable2".
  • The join name will not reflect the name of the table view itself, but rather the source of the table view. Therefore, if a table view is named TableView1 and points at mytable.dbf, the name of the join will be "mytable".

• When a layer is joined to two tables and the first join is removed, then both joins will be removed. For example, Layer1 is joined to TableA. Then Layer1 is joined to TableB. If the join to TableA is removed, the join to TableB is also removed.

• This tool is not limited to working within ArcMap; it works on layers and table views in other ArcGIS applications and in scripts. The Make Feature Layer tool makes a layer from a feature class, and the Make Table View tool creates a table view from an input table or feature class. The layer or table view can then be used as the input to the Add Join and Remove Join tools.

Syntax

RemoveJoin_management (in_layer_or_view, {join_name})

Parameter	Explanation	Data Type
in_layer_or_view	The layer or table view from which the join will be removed.	Mosaic Layer; Raster Catalog Layer; Raster Layer; Table View
join_name (Optional)	The join to be removed.	String

Code Sample

Remove Join Example (Python Window)

The following Python window script demonstrates how to use the RemoveJoin tool in immediate mode in ArcMap on a feature layer in the TOC named veglayer.

arcpy.RemoveJoin_management("veglayer", "vegtable")

Remove Join Example 2 (Stand-alone Script)

This stand-alone script shows the RemoveJoin function as part of a workflow to add a field to a table and calculate its values based on the values in a field from a joined table.

# AddFieldFromJoin.py
# Description: Adds a field to a table, and calculates its values based
#              on the values in a field from a joined table

# Import system modules
import arcpy
from arcpy import env

try:
    # set the environments
    env.workspace = "C:/data"
    env.qualifiedFieldNames = "UNQUALIFIED"
    
    # Define script parameters    
    inFeatures = "Habitat_Analysis.gdb/vegtype"
    layerName = "veg_layer"
    newField = "description"
    joinTable = "vegtable.dbf"
    joinField = "HOLLAND95"
    calcExpression = "!vegtable.VEG_TYPE!"
    outFeature = "Habitat_Analysis.gdb/vegjoin335"
    
    # Add the new field
    arcpy.AddField_management (inFeatures, newField, "TEXT")
    
    # Create a feature layer from the vegtype featureclass
    arcpy.MakeFeatureLayer_management (inFeatures,  layerName)
    
    # Join the feature layer to a table
    arcpy.AddJoin_management (layerName, joinField, joinTable, joinField)
    
    # Populate the newly created field with values from the joined table
    arcpy.CalculateField_management (layerName, newField, calcExpression, "PYTHON")
    
    # Remove the join
    arcpy.RemoveJoin_management (layerName, "vegtable")
    
    # Copy the layer to a new permanent feature class
    arcpy.CopyFeatures_management (layerName, outFeature)
    
except Exception, e:
    
    import traceback, sys
    tb = sys.exc_info()[2]
    print "Line %i" % tb.tb_lineno
    print e.message

Environments

This tool does not use any geoprocessing environments

Licensing Information

ArcGIS for Desktop Basic: Yes

ArcGIS for Desktop Standard: Yes

ArcGIS for Desktop Advanced: Yes