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.