Identifiers Charset

Virtual DataPort supports Unicode characters in the name of most of its elements: databases, user names, roles, data sources, wrappers, views and their fields, etc.

Virtual DataPort allows you to select one of the following char sets for the entire Server and also, one for each database:

  1. Restricted (default one): you can only use basic characters in the name of elements and the fields of the views. See section Restricted Mode.
  2. Unicode: you can use any character in these names. See section Unicode Mode.

Changing from one char set to another, only changes which characters can the users use when creating/editing views from the Administration Tool. It does not affect the behavior of the Server.

Restricted Mode

When the Server or a database is in Restricted mode, the Administration Tools that connect to this Server or database have the following behavior:

  • You can only create elements (user names, data sources, wrappers, views, etc.) whose identifiers follow these rules:
    • The first character has to be one of these:
      • a to z. If you enter uppercase letters, they Tool automatically converts them to lowercase.
      • The Unicode characters with the code point from 200 to 377.
    • The next characters have to be one of these:
      • a to z.
      • Numbers
      • The underscore: _.
      • The Unicode characters with the code point from 200 to 377.

When an element is created in this mode, its identifier is case insensitive. E.g. the query SELECT * FROM incidences is equivalent to SELECT * FROM INCIDENCES.

Unicode Mode

When the Server or a database is in Unicode mode, the Administration Tools that connect to this Server or database have the following behavior:

  • The identifiers of elements (data sources, wrappers, views and their fields, etc.) can contain any character.

  • When the name contains one or more characters that do not belong to the “Restricted char set” (see the section Restricted Mode), the Administration Tool automatically surrounds the name with double quotes in the VQL statement it sends to the Virtual DataPort server.

    For example,

    CREATE VIEW "例" AS... or SELECT * FROM "Categories".
    
  • The Tool automatically adds the double quotes whenever is necessary. You only have to add them when creating views manually from the VQL Shell or a JDBC client.

Note

View names starting with _ are not supported.

When the Server or the database is in Unicode mode, the name of an element is case-sensitive if at least one of these conditions are met:

  • The name is surrounded by double quotes and at least one character is uppercase.
  • Or, the name has characters that do not belong to the “Restricted char set”. If all the characters belong to the “Restricted char set”, the name is case insensitive.

If an element is case-sensitive you always have to surround its name with double quotes. For example,

SELECT * FROM "Incident",
ALTER TABLE "Phone_INC",
etc.

You cannot create elements of the same type with the same name but different case. E.g.: you cannot create the views "incident" and "INCIDENT".

In the VQL statements generated by the Server, if the name of an element is surrounded by double quotes (“”) it means the name is case-sensitive.

If an element listed in the Server Explorer of the Administration Tool has a name with at least one upper case character, it was created with double quotes and therefore, it is a case sensitive element. Because of this, the name of this element has to be surrounded with double quotes.


By default, the Unicode support is disabled and can be enabled for the entire Server or just for some of its databases.

To enable this support for the entire Server, click Server configuration on the menu Administration and then, click Identifiers charset (see Identifiers charset dialog).

In this dialog, click Unicode -Case sensitive and click Ok.

Identifiers charset dialog

Identifiers charset dialog

The Unicode support can also be enabled only in some databases (see section Creating Databases).