Desktop Help 1. 0. Types of geodatabases. The geodatabase is a "container" used to hold a collection of datasets. There are three types: File geodatabases and personal geodatabases. File and personal geodatabases, which are freely available to all users of Arc. View, Arc. Editor, and Arc. The architecture of a geodatabase. The geodatabase is object relational. The different tables stored in file and personal geodatabase are not detailed. XML file. Create a new, empty file geodatabase. Import > XML Workspace Document to import the data and schema from the XML file into a new file geodatabase. I have some large datasets, containing several hundred different feature classes. Each one of these feature classes is then split into 6 different scale. Types of geodatabases. File geodatabase Personal geodatabase; Description: A collection of various types of GIS datasets held as tables in a relational database. Info, are designed to support the full information model of the geodatabase, which comprises topologies, raster catalogs, network datasets, terrain datasets, address locators, and so on. File and personal geodatabases are designed to be edited by a single user and do not support geodatabase versioning. With a file geodatabase, it is possible to have more than one editor at the same time provided they are editing in different feature datasets, stand- alone feature classes, or tables. The file geodatabase was a new geodatabase type released in Arc. GIS 9. 2. Its goals are to do the following: Provide a widely available, simple, and scalable geodatabase solution for all users. Provide a portable geodatabase that works across operating systems. ArcGIS provides a complete set of tools that give you the flexibility to store. Esri File Geodatabase API allows you to interact directly with the stored data. At its most basic level, an ArcGIS geodatabase is a collection of geographic datasets of various types held in a common file system folder, a Microsoft Access. Scale up to handle very large datasets. Provide excellent performance and scalability, for example, to support individual datasets containing well over 3. GB per file with very fast performance. Use an efficient data structure that is optimized for performance and storage. File geodatabases use about one- third of the feature geometry storage required by shapefiles and personal geodatabases. File geodatabases also allow users to compress vector data to a read- only format to reduce storage requirements even further. Outperform shapefiles for operations involving attributes and scale the data size limits way beyond shapefile limits. Personal geodatabases have been used in Arc. GIS since their initial release in version 8. Microsoft Access data file structure (the . They support geodatabases that are limited in size to 2 GB or less. However, the effective database size is smaller, somewhere between 2. MB, before the database performance starts to slow down. Personal geodatabases are also only supported on the Microsoft Windows operating system. Users like the table operations they can perform using Microsoft Access on personal geodatabases. Many users really like the text- handling capabilities in Microsoft Access for working with attribute values. Arc. GIS will continue to support personal geodatabases for numerous purposes. However, in most cases, ESRI recommends using file geodatabases for their scalability in size, significantly faster performance, and cross- platform use. The file geodatabase is ideal for working with file- based datasets for GIS projects, personal use, and in small workgroups. It has strong performance and scales well to hold extremely large data volumes without requiring the use of a DBMS. Plus, it is portable across operating systems. Typically, users will employ multiple file or personal geodatabases for their data collections and access these simultaneously for their GIS work. Arc. SDE geodatabases. When you need a large, multiuser geodatabase that can be edited and used simultaneously by many users, the Arc. SDE geodatabase provides a good solution. It adds the ability to manage a shared, multiuser geodatabase as well as support for a number of critical version- based GIS workflows. The ability to leverage your organization's enterprise relational databases is a key advantage of the Arc. SDE geodatabase. Arc. SDE geodatabases work with a variety of DBMS storage models (IBM DB2, Informix, Oracle, Postgre. SQL, and SQL Server). Arc. SDE geodatabases are primarily used in a wide range of individual, workgroup, department, and enterprise settings. They take full advantage of underlying DBMS architectures to support the following: Extremely large, continuous GIS databases. Many simultaneous users. Long transactions and versioned workflows. Relational database support for GIS data management (providing the benefits of a relational database for scalability, reliability, security, backup, integrity, and so forth)SQL types for Spatial in all supported DBMSs (Oracle, SQL Server, Postgre. SQL, Informix, and DB2)High performance that can scale to a very large number of users. Through many large geodatabase implementations, it has been found that DBMSs are efficient at moving in and out of tables the type of large binary objects required for GIS data. In addition, GIS database sizes can be much larger and the number of supported users greater than with file- based GIS datasets. For information about the Arc. SDE geodatabase architecture and how Arc. SDE geodatabases leverage relational database technology, see Architecture of the geodatabase. Arc. SDE provides long and short transaction management on the DBMS transaction framework. One of the primary roles for Arc. SDE is to support the geodatabase versioning framework in each DBMS. Quite frequently, an individual editing transaction in a GIS can involve changes to multiple rows in multiple tables. For example, updating a parcel may require that you change the polygon's representation along with changing the corresponding boundary lines and parcel corners. In addition, attribute records for each of these features must be updated as well. This edit involves making changes to multiple records in many tables. In these cases, users want to treat this collection of edits as a single transaction. When the changes are committed or rolled back, they are managed together as a unified operation. At the same time, users want the ability to undo and redo individual edit operations within an edit session. To further complicate this situation, the edits may need to be performed in a system that is disconnected from the central, shared database. Furthermore, during these specialized GIS data maintenance processes, the GIS database must remain continuously available for daily operations, where each user might have a personal view or state of the shared GIS database. The Arc. SDE geodatabase supports management and updates for these and many other data management scenarios in a multiuser environment by using a method called versioning. Versioning is a mechanism in which all database changes are recorded as rows in tables. For example, each time you update a value in a row, the old row is "retired" and a new, updated row is added. In this way, Arc. SDE technology manages such high- level, complex GIS transactions on the simple DBMS transaction framework by storing change information as delta records in the database. This mechanism for maintaining records of all changes, along with their metadata, is the genesis of the term versioning. Arc. SDE uses metadata about versions to isolate multiple edit sessions, support complex transactions, share replicas,synchronize contents across multiple databases, perform automatic archiving, and support historical queries. See An overview of editing and maintaining data for more information. How is Arc. SDE technology included in Arc. GIS? In the past, Arc. SDE was sold as a separate Esri product. Starting with Arc. GIS 9. 2, Arc. SDE technology is included as capabilities within Arc. GIS rather than being offered separately. Arc. SDE technology has been integrated into Arc. GIS Desktop, Arc. GIS Engine, and Arc. GIS Server so that users can scale their DBMS- based geodatabases across their organizations. Beginning at Arc. GIS 9. 2, Arc. Editor and Arc. Info includes an installation of Microsoft SQL Server Express. These software products also include Arc. SDE capabilities to support Arc. SDE geodatabases in SQL Server Express for up to three simultaneous desktop users. Beginning with Arc. GIS 9. 3, Arc. GIS Engine includes an installation of SQL Server Express. The optional Geodatabase Update extension for Arc. GIS Engine is required for Arc. GIS Engine applications that edit geodatabases. Microsoft limits the use of SQL Server Express to one CPU (or core within a socket) and 1. GB of RAM. The maximum database size for SQL Server 2. Express is limited to 4. GB. The maximum database size for SQL Server 2. Express R2 is 1. 0GB. Consult your Esri license agreement for specific information on the instance size limitations for your implementation.)Within Arc. Editor and Arc. Info, the Arc. Catalog application provides the ability for you to fully administer and manage Arc. SDE geodatabases using SQL Server Express. This provides full Arc. SDE geodatabase capabilities for up to a few users at a time. You set up and manage these Arc. SDE geodatabases within Arc. Catalog or the Catalog window. No extra software or database administration expertise is required. Arc. GIS Server Workgroup also includes Arc. SDE support for SQL Server Express. With this level of Arc. SDE, you can use SQL Server Express for up to 1. Windows desktop users and editors (users of Arc. View, Arc. Editor, Arc. Info, a custom Arc. GIS Engine application, Auto. CAD, Micro. Station, and so on) plus any number of additional server connections from Web applications. Consult your license agreement for specific information on the number of connections for your implementation.)For Arc. GIS Server Workgroup, you can use Arc. Editor or Arc. Info to create, administer, and manage Arc. SDE geodatabases for SQL Server Express within Arc. Catalog or the Catalog window. No extra database administration expertise is required. Arc. GIS Server Enterprise includes full enterprise Arc. SDE technology with no limits. You can still run the traditional Arc. SDE technology for Oracle, SQL Server, Postgre. SQL, IBM DB2, and IBM Informix. Arc. SDE support at the enterprise server level can scale to databases of any size and number of users and runs on computers of any size and configuration. With Arc. GIS Server Enterprise, you provide your own DBMS license for this level of Arc. SDE use. Choices include the following: Oracle. Microsoft SQL Server. IBM Informix. IBM DB2. Postgre. SQLThe DBMS is typically administered and managed by a database administrator (DBA). Summary points. You do not need to monitor and manage the use of your memory and CPUs for SQL Server Express.
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