17.10 - Rules for HELP Report Names and Titles - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Data Definition Language Detailed Topics

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Programming Reference
Publication ID
B035-1184-171K
Language
English (United States)

When you execute a HELP statement, the system returns the following name and title information for database objects.

For names, such as column names:

  • Primary name, for example, Column Name, based on object definitions that exist in the data dictionary. CHAR(30) name format for support of legacy applications.
  • Column Dictionary Name
  • Column SQL Name
  • Column Name UEscape

For titles of objects which support a title, such as tables and columns:

  • Title, up to VARCHAR(256)
  • Dictionary Title
  • SQL Title
  • Title UEscape

These fields help you to manage the differences between the data dictionary representation of name or title and the representation in the session (client) character set. You can use SQL Name and SQL Title values directly in subsequent SQL statements.

The system determines the contents of HELP name fields based on the rules in the following table.

Field Description
  • object_type Dictionary Name
  • Dictionary Title
The data dictionary name or title, translated to the session character set.

Object names: VARCHAR(128)

Titles: VARCHAR(256)

If any character in the name or title is not translatable into the session character set, the system converts it into the replacement character for the session character set.

For example, when the session character set is ASCII, the system replaces each untranslatable character with the SUBSTITUTE character 0x1A:

^Z

where the ^Z is used to represent an unprintable control character.

  • object_type 
SQL Name
  • SQL Title
The name or title as it exists in the data dictionary, converted to a string that can be directly used in an SQL request, expressed in the shortest form (with matching case) for the current session character set.

Object Names: VARCHAR(644)

If all characters in an object name are translatable into the session character set, the SQL Name for the object name is the same as the Dictionary Name. If SQL statement syntax requires quotation marks, the SQL Name field begins and ends with QUOTATION MARK (U+0022) characters.

For information on using quotation mark characters with object names, see SQL Fundamentals.

If the object name contains characters that are not translatable into the current session character set, the system expresses the SQL Name as a UNICODE delimited identifier, although without the normal closing UEscape clause, starting with LATIN CAPITAL LETTER U (U+0055), followed by AMPERSAND (U+0026), followed by QUOTATION MARK (U+0022), and ends with a QUOTATION MARK (U+0022).

For example:

U&"\7A0E\91D1"

Titles: VARCHAR(1284)

The system expresses the SQL Title similarly to the SQL Name, except that a title is a string, not a name, so:

  • If all the characters in the title are translatable into the current session character set, the SQL Title field value begins and ends with an APOSTROPHE (U+0027).
  • If a title contains characters that are not translatable into the session character set, the system expresses the SQL Title as a UNICODE delimited literal, which places a LATIN CAPITAL U (U+0055) and then an AMPERSAND (U+0026) before the beginning APOSTROPHE.

The system replaces each character that is not translatable into the session character set with the corresponding UNICODE identifier. Each UNICODE identifier is preceded by the default delimiter character for the session character set.

For example, when specifying the Polish currency as ‘Polish_Zloty,’ the LATIN SMALL LETTER L WITH STROKE, shown as an “l” in “zloty’ is expressed as \0142, for example:

U&'Polish_Z\0142oty '
  • object_type UEscape
  • Title UEscape
VARCHAR(1)

Indicates the delimiter character that precedes each UNICODE identifier substituted for an untranslatable character in the SQL Name/SQL Title. For example:

Table UEscape: \

If all characters in the SQL Name/SQL Title are translatable into the session character set, the SQL Name/SQL Title field e does not include any delimiters and the UEscape field is NULL.

Table UEscape: ?

where the ? character represents NULL.