Saturday 21 September 2013

2.5 Teradata Parallel Transporter Scripting language and Syntax rules


TPT scripting Language and Syntax rules:

TPT uses an SQL-like scripting language to define extract, updating, and load functions in a job script.
All Teradata PT operators use the same language.

  1. Case  sensitivity syntax:

  • Attribute Names (Ex: TDPID) are case insenstive. TDPID and tdpID both mean the same
  • Most of Attribute Values (Ex: 'GT11_loadoper_privatelog' in above example ) are case insensitive , but certain things like filename, directory names can be case sensitive depending upon the platform(Ex: Unix is case Senstive. Files 'myfile.txt' and 'MYFILE.txt' both are different.
  • Non-attribute object parameters, such as the syntax elements in a DEFINE JOB statement, are case-sensitive.

  1. Defining Objects:

  • Objects should be defined  before they are used.

  1. Keywords Restrictions:

  • We should not use TPT keywords like SCHEMA, OPERATOR as the identifiers for column names, attributes and other values.

  1. Keywords INTEGER and VARCHAR are used to declare the attributes of the  operators:
    ex:
                       VARCHAR PrivateLogName    = 'GT11_loadoper_privatelog',
                       INTEGER MaxSessions       =  32,
                       INTEGER MinSessions       =  1,

                      VARCHAR and INTEGER are mandatory required when an attribute if declared but                       attribute value is not specified.

                       However if the attribute declaration includes values then we don’t need to write                        VARCHAR and INTEGER..
                       This means instead of the above we could have just written as follows:

                       PrivateLogName    = 'GT11_loadoper_privatelog',
                       MaxSessions       =  32,
                       INTEGER MinSessions       =  1,

                        This is allowed because we are providing the attribute values along with the                            declarations.

  1. Quotation  Marks

  • Character string literals must be enclosed in single quotes.
  • Values for VARCHAR attributes must be enclosed in single quotes, and embedded quotes must be escaped with two consecutive single quotes.

                       Ex:PrivateLogName    = 'GT11_loadoper_privatelog',

  • Values for INTEGER attributes require no quotes.

                       Ex: INTEGER MinSessions       =  1,

  1. SQL notation:

  • IF SQL statements span multiple lines there should be a space or a tab character between the last character of the line and the 1st character of the next line.
                             If not provided the it joins the two character strings, resulting in either an                                error or the processing of an unintended SQL statement.

                          Ex:

                          'CREATE TYPE INSV_INTEGER AS INTEGER FINAL
                          INSTANCE METHOD IntegerToFloat()

                          In above example  following code would produce an error if no space or tab was added between “FINAL” and “INSTANCE” because the Teradata Database would see the invalid keyword FINALINSTANCE.

  1. Comments


  • TPT supports C- style comments. /* */

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