Connection's features

• access to each type of database is performed by a provider which exists as a plugin (similar to ODBC or JDBC's driver)

• providers exist for several database types such as PostgreSQL, MySQL, or SQLite see the providers' status page for more detail

• opening connections can be done by defining data sources (DSN), per-user or system wide, or by using direct connection strings
• transactions and save points are supported on a per-connection basis (transaction status tracked for each connection)
• distributed transactions (transactions involving several connections) are supported
• provider's features can be queried at run time

SALES, INSERT, UPDATE and DELETE statements

Libgda's features regarding Data Manipulation queries (SELECT, INSERT, UPDATE and DELETE) are:

• powerfull SQL analyser which:
  • can be customized by each database provider
  • is able to delimiter individual SQL statements within a string containing several statements
  • supports a generic (and database agnostic) way of specifying place holders (variables)
• support for specifying how a SELECT query's result set will be accessed (random access or cursor based for large data sets)
• the data set returned after the execution of a SELECT statement may be modified (thus modifying the data in the database)
• the execution of a non SELECT query returns information about the number of impacted rows

Data definition statements

Libgda's features regarding Data Definition statements (all the queries which are not DML queries) are:

• support to create and drop databases
• support to create, alter and drop tables
• support to create and drop indexes

• each operation fully supports all the features of the actual DBMS being used

• extension to other kind of operation very easy becaused based on an XML specification

Note: the actual support depends on the implementation of each DBMS provider

Dictionary

Libgda implements a meta data dictionary object which exposes in a convenient way all the database structure:

• data types
• tables and view (and their fields)
• constraints
• ...

Specifically the dictionary can:

• be updated (synchronized) with the database to reflect database structure's changes
• be extended with custom data
• be stored in the database it refers to or to an external file