ArcGIS file Geodatabase, personal geodatabase and ArcSDE office

Types of Geodatabases

A geodatabase is a "container" for saving a collection of datasets. There are three types of the following:

1. File geodatabases-stored as folders in the file system. Each dataset is saved as a file, and the file size can scale up to 1 TB. It is recommended that you use a file geodatabase instead of a personal geodatabase.
2. Personal Geodatabase-all datasets are stored in a Microsoft Access data file with a maximum size of 2 GB.
3. ArcSDE Geodatabases-also known as multiuser geodatabases. This type of database is stored in a relational database using Oracle, Microsoft SQL Server, IBM DB2, IBM Informix, or PostgreSQL. These geodatabases need to use ArcSDE, and there is no limit to size and number of users.

compare three types of geodatabases

Key Features	ArcSDE Geodatabase	File Geodatabase	Personal Geographic Database
description		various types of GIS saved in the File system folder A collection of datasets (native data formats recommended for ArcGIS that are stored and managed in a file system folder. )
number of users	multiuser: multiple-bit readers and multiple-bit writers	single user and smaller workgroup: Each feature DataSet, A stand-alone feature class or table has multiple readers or one writer. Floating using any particular file will eventually result in a large number of readers being demoted.	individual users and smaller workgroups (with smaller datasets): multiple-bit readers and one write Stakeholders Floating use eventually causes a large number of readers to degrade.
storage format	  Oracle microsoft SQL Server IBM DB2 IBM Informix postgresql		everything in each personal geodatabase is saved in a single Microsoft Access file (. mdb).
size limit	up to DBMS limit	1 TB per data set. Each file Geodatabase can hold many datasets. For very large image datasets, you can increase the 1 TB limit to up to a maximum of TB. Each feature class can be extended up to hundreds of millions of vector features per dataset.	2 GB per Access database. The effective limit before performance drops is typically between 250 and MB per Access database file.
Version Management support	Full support for all DBMS. This includes cross-database replication, updating with check-out and check-in, and historical archiving.	Only geodatabase formats are supported for clients that use check-out and check-in to submit updates, and for clients that can use one-way replication to send updates to them.	Only geodatabase formats are supported for clients that use check-out and check-in to submit updates, and for clients that can use one-way replication to send updates to them.
Platform	Windows, UNIX, Linux, and direct connection to the DBMS, which may run on any platform in the user's local network.	Cross-platform.	Applies to Windows only.
Security and Permissions	Provided by the DBMS	Operating file system security.	Windows file system security.
Database Administration Tools	Complete DBMS capabilities for backup, recovery, replication, SQL support, security, and more	File System Management.	Windows file System Management.
Note	Need to use ARCSDE technology; ARCSDE for SQL Server Express comes with the following three items ArcGIS for Desktop Standard and premium ArcGIS Engine ArcGIS for Server Workgroup ArcSDE for all other DBMS with ArcGIS for Server	You can also store data in a read-only compressed format to reduce storage requirements.	Typically used as a property sheet manager (through Microsoft Access). The user prefers string handling for text properties.

comparison of three types of geodatabases

Learn about creating a Geodatabase

File geodatabases and personal geodatabases

File geodatabases and personal geodatabases are designed to support a complete information model for geodatabases, including topologies, raster catalogs, network datasets, terrain datasets, address locators, and more, ArcGIS for Desktop Basic, Standard and Premium editions Both geodatabases are available free of charge for all users. Single users can edit file geodatabases and personal geographic data, which do not support geodatabase versioning. With a file geodatabase, you can have multiple editors at the same time if you want to edit in a different feature dataset, stand-alone feature class, or table.

A file geodatabase is a new geodatabase type released by ArcGIS 9.2. It is designed to perform the following actions:

• expands to handle very large datasets.
• excellent performance and scalability. For example, to support a single dataset that contains more than 300 million features, and to support datasets that can be scaled up to more than five gigabytes (and have excellent performance) for each file. The

Since the personal geodatabase was first published in ArcGIS 8.0, ArcGIS has been using personal geodatabases, which use the Microsoft Access data file structure (. mdb file). The maximum size of geodatabases they support is 2 GB. However, a valid database size is smaller (between 250 and MB) before the database performance begins to degrade. Personal geodatabases can only be used under the Microsoft Windows operating system. Users like the table actions they can perform on personal geodatabases through Microsoft Access. Many users do like the text Processing feature in Microsoft Access that handles property values.

For many purposes, ArcGIS will continue to support personal geodatabases. However, in most cases, Esri recommends using file Geodatabases because the size of the file Geodatabase is scalable, performance is significantly improved, and can be used across platforms. File geodatabases are ideal for working with file-based datasets for GIS projections and are ideal for personal use and for use in small workgroups. It has high performance and is able to scale well to store large amounts of data without the need for a DBMS. In addition, it can be ported across multiple operating systems.

Typically, users use multiple files or personal geodatabases for data collections and access them at the same time for their GIS work.

ArcSDE Geodatabase

ArcSDE Geodatabases provide an excellent solution if you need a large multi-user geodatabase that can be edited and used simultaneously by multiple users. New features can be used to manage a shared multiuser geodatabase and support a variety of key version-based GIS workflows. The ability to leverage your organization's enterprise relational database becomes an important advantage of ArcSDE geodatabases.

ArcSDE geodatabases are available for multiple DBMS storage models (IBM DB2, Informix, Oracle, PostgreSQL, and SQL Server). ArcSDE geodatabases are used in a wide range of applications, primarily for personal, workgroup, departmental, and enterprise settings. They take full advantage of the DBMS's infrastructure to support the following:

• Super-Large Continuous GIS database
• Multi-bit Sync users
• Long transactions and versioned workflows
• relational database support for GIS data management (providing the benefits of establishing a relational database for scalability, reliability, security, backup, and integrity)
• SQL space types in all supported DBMS (Oracle, SQL Server, PostgreSQL, Informix, and DB2)
• High performance adaptable to a wide range of user requirements

With the installation of many large geodatabases enabled, we found that the DBMS was extremely efficient in moving large binary objects needed for GIS data into and out of the table. In addition, the GIS database has more capacity and supports more users than file-based GIS datasets.

For information about the ArcSDE Geodatabase schema and how the ARCSDE geodatabase leverages relational database technology, see the Geodatabase schema.

ArcSDE enables long transaction management and short transaction management of the DBMS transaction framework

One of the primary roles of ArcSDE is to support the Geodatabase versioning framework in each DBMS.

In most cases, a single edit transaction in a GIS may involve making changes to multiple rows in multiple tables. For example, updating a parcel might require changing the representation of polygons and changing the corresponding boundary lines and parcel corners. In addition, you must update the attribute records for each feature in these features. This edit operation requires changes to multiple records in more than one table. In these cases, the user wants to treat this edit collection as a single transaction. When these changes are committed or rolled back, they are treated as a unified operation for management.

At the same time, users want to be able to undo and redo individual edits in an edit session. For this to become more complex, you may need to perform an edit operation on a system that is disconnected from the central shared database.

Also, in these specialized GIS data maintenance processes, the GIS database must remain available for daily operations, and in these daily operations, each user is likely to acquire a personal view or state of the shared GIS database.

By using a method known as versioning, ArcSDE geodatabases support the management and updating of these data management scenarios and many other data management scenarios in a multi-user environment. With versioning this mechanism, all database changes are recorded as rows in the table. For example, each time a value in a row is updated, the old value is invalidated and an update row is added.

This enables ArcSDE technology to manage complex advanced GIS transactions in a simple DBMS transaction framework by storing change information in a database in incremental records.

Note:

This mechanism is used to maintain records of all changes and their metadata, which is the origin of terminology versioning.

ArcSDE uses version metadata to isolate multiple editing sessions, support complex transactions, share replicas, synchronize content between multiple databases, perform AutoArchive, and support historical queries.

For more information, see Edit and maintain data overview.

How do I include ArcSDE technology in ArcGIS?

In the past, ArcSDE was sold as a separate ESRI product. Starting at ArcGIS 9.2, ArcSDE technology has become a feature of ArcGIS and is no longer available separately. ArcSDE technology has been integrated into ArcGIS for Desktop, ArcGIS Engine, and ArcGIS for Server so that users can extend the DBMS-based geodatabase within their organization.

Starting at ArcGIS 9.2, the ArcGIS for Desktop Standard and Premium editions contain the Setup program for Microsoft SQL Server Express. These software products also include ARCSDE capabilities that support ArcSDE geodatabases in SQL Server Express, and support up to three desktop users at a time.

Starting at ArcGIS 9.3, ArcGIS Engine contains the setup program for SQL Server Express. The optional geodatabase Update extension for ArcGIS engine is a required module for the ArcGIS engine application used to edit the geodatabase.

Microsoft has limited the use of SQL Server Express, which requires only one CPU (or the core in sockets) and 1GB of RAM. SQL Server 2005 Express or SQL Server Express databases can be up to 4GB in maximum. The SQL Server Express R2 database has a maximum of 10GB. (For specific information about instance size limits at the time of implementation, see the Esri License agreement.) ）

In ArcGIS for Desktop Standard and premium, you can use the ArcCatalog application to fully manage an ArcSDE geodatabase using SQL Server Express. This allows a full range of ArcSDE Geodatabase functionality to be available to multiple users at once. You can set up and manage these ArcSDE geodatabases in ArcCatalog or in the Catalog window. There is no need for additional expertise in software or database management.

ArcGIS for Server Workgroup also includes ArcSDE support for SQL Server Express. With this level of ArcSDE, you can support up to 10 Windows desktop users and editors at the same time by using SQL Server Express (ArcGIS for Desktop Basic, Standard Edition, Premium Edition, custom ArcGIS Eng INE applications, AutoCAD, MicroStation, etc.) and can support any number of additional server connections from the WEB application. (For specific information about the number of connections required to implement, see the license agreement.) ）

For ArcGIS for Server Workgroup, you can create and manage SQL Server Express ARCSD in ArcCatalog or in the Catalog window using ArcGIS for Desktop Standard or Premium edition E Geodatabase. There is no need for additional expertise in database management.

ArcGIS for Server contains full enterprise-level ArcSDE technology without any restrictions. You can still run legacy ArcSDE technologies for Oracle, SQL Server, PostgreSQL, IBM DB2, and IBM Informix. Enterprise Server-level ArcSDE support can be scaled to any size database and any number of users, and can be run on any size and configured computer. With ArcGIS for Server, you can provide your own DBMS license to use this level of ArcSDE. Options include the following:

• Oracle
• Microsoft SQL Server
• IBM Informix
• IBM DB2
• PostgreSQL

A DBMS is typically managed by a database administrator (DBA).

Summary

You do not have to monitor and manage memory and CPU usage for SQL Server Express. For a single Cpu,sql server Express software, the computer's use is automatically limited to 1 GB of RAM, and the database size is 4GB or 10GB, depending on the version of SQL Server Express you are using.

Unlike Microsoft Access databases, the performance of SQL Server Express does not degrade as the database size approaches its upper limit.

ArcSDE for SQL Server Express is free as part of ArcGIS for Desktop Standard and premium. If you choose to install SQL Server Express, you can use ArcCatalog to manage the SQL Server Express database.

When you install ArcGIS for server Workgroup, you can install and use SQL Server Express. After you install SQL Server Express, you can use ArcCatalog to manage your workgroup server's SQL Server Express database in ArcGIS for Desktop or premium level licensing.

These different levels enable users to take full advantage of an ArcSDE geodatabase for any number of users, regardless of quantity. In this way, the organization will have an extensible data architecture that applies both to the organization's single-user system and to its large enterprise systems.

ArcSDE Level Summary

ArcGIS file Geodatabase, personal geodatabase and ArcSDE office