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Editing Tables and Attributes in ArcMap
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Author: Kevin MacLeod
Sources of tabular information
Tasks you can perform with tables and attribute information
Tabular information is the basis of geographic features, allowing you to visualize, query, and analyze your data. In the simplest terms, tables are made up of rows and columns, and all rows have the same columns. In ArcGIS, rows are known as records and columns are fields. Each field can store a specific type of data, such as a number, date, or piece of text.
Feature classes are really just tables with special fields that contain information about the geometry of the features. These include the Shape field for point, line, and polygon feature classes and the BLOB field for annotation feature classes. Some fields, such as the unique identifier number (ObjectID) and Shape, are automatically added, populated, and maintained by ArcGIS.
The attribute table for a parcels layer
ArcGIS allows you to associate records in one table with records in another table through a common field, known as a key. You can make these associations in several ways, including by joining or relating tables temporarily in your map or by creating relationship classes in your geodatabase that maintain more permanent associations. For example, you could associate a table of parcel ownership information with the parcels layer, since they share a parcel ID field.
Learn more about joining and relating tables
Learn more about choosing between joins, relates, and relationship classes
Sources of tabular information
There are lots of sources of tabular data, and ArcGIS can take advantage of many formats. Tabular information could be stored as tables in folders or databases, text files, queries on databases, and so on. In addition, if you have spatial data, you probably already have tabular attributes that describe those geographic features.
File-based tables are stored in folders on disk. Some examples of file-based sources of tabular information include the following:
dBASE tables, the format used with shapefiles
INFO, the format used with coverages
Text files, such as those created in a text editor and delimited by commas or tabs
Many other sorts of tables, including those generated in other programs, such as Microsoft Excel, either accessed directly in ArcGIS or through the OLE DB functionality
Tables in a database or geodatabase can contain some types of information that file-based tables do not support. For example, database or geodatabase tables can store BLOB or raster field types. In addition, databases and geodatabases provide capabilities to extend the functionality of tables, such as maintaining data integrity and managing transactions.
You can perform queries on these database or geodatabase tables to create new tables. The Make Query Table tool, for example, allows you to apply a SQL expression to one or more tables. The query can be used to join the tables or return a subset from the original data.
To learn more about what you can do with these different kinds of tables, see About tabular data sources.
Tasks you can perform with tables and attribute information
There are many mapping, analysis, and data management tasks you can perform using tabular data.
Tables allow you to map and visualize your data. For example, you can classify or categorize attributes to symbolize a layer. You can use population values to symbolize major cities with a larger symbol than would be used for smaller towns and villages. You can also specify that a different color be used to represent each type of land use in a parcel layer. In addition, you can use the attribute values to generate text to label each parcel feature. In the graphic below, the parcels are symbolized by the type of land use, then labeled with their parcel ID values.
Parcels symbolized by type of land use and labeled with parcel ID values
Attribute data helps you perform spatial queries and analyses. For e
Author: Kevin MacLeod
Sources of tabular information
Tasks you can perform with tables and attribute information
Tabular information is the basis of geographic features, allowing you to visualize, query, and analyze your data. In the simplest terms, tables are made up of rows and columns, and all rows have the same columns. In ArcGIS, rows are known as records and columns are fields. Each field can store a specific type of data, such as a number, date, or piece of text.
Feature classes are really just tables with special fields that contain information about the geometry of the features. These include the Shape field for point, line, and polygon feature classes and the BLOB field for annotation feature classes. Some fields, such as the unique identifier number (ObjectID) and Shape, are automatically added, populated, and maintained by ArcGIS.
The attribute table for a parcels layer
ArcGIS allows you to associate records in one table with records in another table through a common field, known as a key. You can make these associations in several ways, including by joining or relating tables temporarily in your map or by creating relationship classes in your geodatabase that maintain more permanent associations. For example, you could associate a table of parcel ownership information with the parcels layer, since they share a parcel ID field.
Learn more about joining and relating tables
Learn more about choosing between joins, relates, and relationship classes
Sources of tabular information
There are lots of sources of tabular data, and ArcGIS can take advantage of many formats. Tabular information could be stored as tables in folders or databases, text files, queries on databases, and so on. In addition, if you have spatial data, you probably already have tabular attributes that describe those geographic features.
File-based tables are stored in folders on disk. Some examples of file-based sources of tabular information include the following:
dBASE tables, the format used with shapefiles
INFO, the format used with coverages
Text files, such as those created in a text editor and delimited by commas or tabs
Many other sorts of tables, including those generated in other programs, such as Microsoft Excel, either accessed directly in ArcGIS or through the OLE DB functionality
Tables in a database or geodatabase can contain some types of information that file-based tables do not support. For example, database or geodatabase tables can store BLOB or raster field types. In addition, databases and geodatabases provide capabilities to extend the functionality of tables, such as maintaining data integrity and managing transactions.
You can perform queries on these database or geodatabase tables to create new tables. The Make Query Table tool, for example, allows you to apply a SQL expression to one or more tables. The query can be used to join the tables or return a subset from the original data.
To learn more about what you can do with these different kinds of tables, see About tabular data sources.
Tasks you can perform with tables and attribute information
There are many mapping, analysis, and data management tasks you can perform using tabular data.
Tables allow you to map and visualize your data. For example, you can classify or categorize attributes to symbolize a layer. You can use population values to symbolize major cities with a larger symbol than would be used for smaller towns and villages. You can also specify that a different color be used to represent each type of land use in a parcel layer. In addition, you can use the attribute values to generate text to label each parcel feature. In the graphic below, the parcels are symbolized by the type of land use, then labeled with their parcel ID values.
Parcels symbolized by type of land use and labeled with parcel ID values
Attribute data helps you perform spatial queries and analyses. For e
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