The Join Features tool will transfer attributes from one layer or table to another based on spatial and attribute relationships. Optionally, statistics can be calculated for the joined features.
An analyst has crime data throughout their city. To analyze and study the impact of these crimes, the analyst needs to understand the relationship that the crime locations have with the various city jurisdictions such as school districts, police beats, neighborhoods, and so on. By using the Join Features tool, additional information about each location can be appended to each crime, and the impact on various jurisdictions can be further studied and analyzed.
ArcGIS Living Atlas of the World state and county layers include population data that can be joined to your crime data.
The Join Features tool is designed to transfer and append information from one layer to another. The information that is transferred is based on the type of spatial relationship defined or based on a common attribute that is shared between the two datasets.
You can add a layer that is not in Map Viewer to the tool pane by selecting Choose Analysis Layer in the drop-down menu.
When joining features, you can join features based on a spatial relationship, an attribute relationship, or a combination of the two.
Choose a spatial relationship
The spatial relationship that will determine whether features are joined to each other. The available relationships depend on the geometry type (point, line, or area) of the layers being joined. Available spatial relationships are as follows:
Choose the fields to match
The attribute relationship that will determine whether features are joined to each other. Features are matched when the field values in the join layer are equal to field values in the target layer.
The join operation determines how joins between the target and join layers will be handled if multiple features in the join layer are found to have the same relationship to the target layer. The following are the two join operations from which to choose:
- Join one to one—This option joins the features in the target layer to a single feature in the join layer. The count of joined features will be added by default. Optionally, if statistics are added using the Add statistics parameter, matched joined features will be summarized to each feature in the target layer. If the matching record is defined using the Define which record is kept parameter, you can choose to either keep the first matching record (default) or to keep a matching record based on an expression. An expression can use either a numeric field (option for largest or smallest record) or a date field (option for newest or oldest).
- Join one to many—This option joins all the matching features in the join layer to the target layer. The result layer will contain multiple records of the target feature.
Keep all target features is used to determine whether output includes only matching features, or all features from the target layer. When this option is not checked (default), only matching features between the target layer and the join layer are returned in the output (an inner join). When checked, all features in the target layer are returned in the output, even if the target feature does not have a match in the join layer (a left outer join).
If Use current map extent is checked, only the features visible within the current map extent will be analyzed. If it's not checked, all features in both the target layer and the join layer will be analyzed, even if they are outside the current map extent.
Create results as hosted feature layer view allows the data to stay up to date as the source data changes. Hosted feature layer views containing joins will be read-only and do not consume credits for analysis and storage. If statistics are included as part of the output, the hosted feature layer view will contain an extra table layer in the view with the statistics. Attachments on the target layer will be preserved if the target layer has attachments enabled and a GlobalID field. For more information on hosted feature layer views, see Limitations.
Click Show Credits before you run your analysis to check how many credits will be consumed.
Summary statistics can only be calculated if a Join one to one operation is specified.
Joins cannot be created using fields that have a field type of ObjectID. If the values from an ObjectID field must be used in a join, you can create an integer field and calculate the field based on the ObjectID value.
You can create a hosted feature layer view from the analysis results if all of the following conditions are met:
- You are the owner of both layers.
- Both layers are hosted feature layers.
- You are performing an attribute join.
When storing results as a hosted feature layer view, Use current map extent is unavailable.
How Join Features works
Standard deviation is calculated using the following equation:
Statistics are calculated for only those features that meet the specified spatial or attribute relationship used in the Join one to one operation. You can calculate numeric and string statistics. By default, only the Count is calculated. Using the table above, numeric statistics were calculated on the field Occupants and string statistics were calculated on the field Building_Name for the values of Apartments for the field Type.
|Numeric statistic||Results of Occupants of Type Apartment|
The count statistic counts the number of nonnull values. The counts of [0, 1, 10, 5, null, 6] = 5.
Use Join Features to transfer attributes from one layer or table to another based on spatial and attribute relationships. Other tools may be useful in solving similar but slightly different problems.
Map Viewer analysis tools
Use the Enrich Layer tool to get demographic and landscape information for the people, places, and businesses associated with your point, line, or area data locations.