SQL - General Information
- is a standard query language for relational databases
- It supports logical data model concepts, such as relations, keys, ...
- Supported by major brands, e.g. IBM DB2, Oracle, MS SQL Server, Sybase, ...
- 3 versions: SQL1 (1986), SQL2 (1992), SQL 3 (1999)
- Can express common data intensive queries
- SQL 1 and SQL 2 are not suitable for recursive queries
SQL and spatial data management
- ESRI Arc/Info included a custom relational DBMS named Info
- Other GIS software can interact with DBMS using SQL
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Última modificación: Thursday, 17 de November de 2005, 16:45