Limits on the size of database objects in an enterprise geodatabase are mostly dependent on hardware limitations. The limit on database object name size is the smaller of either the limit enforced by the database management system or the geodatabase limit. Limits vary from one database management system to the next. The types of characters allowed in object names vary by database management system but are also affected by how ArcGIS stores and queries the object information.
Size limits
Most size limits in a database depend on the database management system edition and hardware limitations. See the documentation for your database management system to determine size limits.
Number of characters in object names
The following table lists the maximum number of characters allowed by ArcGIS for each type of object name.
| Object type | Maximum bytes allowed by ArcGIS |
|---|---|
Database name | ArcGIS does not create databases for Oracle but can read the maximum database name allowed by Oracle. |
Table, feature class, or view name | 128 |
Feature dataset name* | 159 |
Index name | 16 if created in ArcGIS. ArcGIS can read up to the database limit for indexes created outside ArcGIS. |
Field (column) name | 30 |
Field alias* | 255 |
Password | 256 |
User or role name | 31 30 if using Oracle 12.1 or an earlier release. |
Version name* | 62 |
*Feature dataset names, field aliases and versions are not database objects; rather, they are defined in geodatabase system tables.
Character type limits in object names
Database management systems have different definitions of acceptable characters for object names. Most names must begin with a letter and cannot contain spaces, backslashes, or reserved database management system keywords. Some databases allow special characters such as forward slashes (/), underscores (_), dollar signs ($), dashes (-), dots (.), or mixed cases. Sometimes the database allows you to use special characters or reserved keywords, or force mixed-case, uppercase, or lowercase names if you provide the object name enclosed in delimiters, such as double quotation marks.
However, ArcGIS does not delimit object names. Do not create any tables, feature classes, indexes, databases, users*, roles, or other object names that require delimiters if you will be using them with ArcGIS. The object will be created in the database, but you cannot access it from ArcGIS.
*Microsoft SQL Server user names containing special characters are delimited to fully support Active Directory Groups and Windows Authenticated logins; however, ArcGIS does not support user names containing single quotation marks or apostrophes.