Statements¶

There are two types of statements in VQL:

1. DDL (Data Definition Language) statements. They allow creating new data sources, wrappers, views, etc. The DDL commands are:

   • CREATE: creates or replaces new base views, views, stored procedures, wrappers, data sources, published web services, users, etc.

   • DROP: removes elements such as base views, views, stored procedures, wrappers, data sources, published web services, users, etc.

   • ALTER: modifies specific properties of views such as its internationalization configuration, cache, swapping configuration, etc. It also allows modifying database and user permissions.

   • DESC: shows the description of data types, views, stored procedures, maps, operators, wrappers, data sources, etc.

   • LIST: enumerates the elements of the catalog (data sources, views, etc.)

   • GRANT and REVOKE: Allow to establish or revoke user permissions over databases, stored procedures and/or views.

2. DML (Data Manipulation Language) statements. They allow querying and updating data. Virtual DataPort provides the following DML statements:

   • SELECT to execute queries and define new views.

   • INSERT, UPDATE and DELETE for inserting, updating and deleting rows from a view, respectively.

   • BEGIN, COMMIT, ROLLBACK for beginning, committing and rolling back transactions, respectively. See more information about this in the section Transactions in Virtual DataPort.

   • CALL to execute Virtual DataPort stored procedures.