Here is a sample Teradata PT schema definition for the sample SOURCE_TABLE table:
DEFINE SCHEMA EMPLOYEE_SCHEMA
DESCRIPTION 'SAMPLE EMPLOYEE SCHEMA'
(
EMP_ID INTEGER,
EMP_NO BYTEINT,
COL003 VARCHAR(47),
COL004 VARCHAR(17),
COL005 VARCHAR(25)
);
In this example, the COL003 column is defined as VARCHAR(47), because it is the maximum representation for the COL003 column in the table.
Here is the calculation for the maximum representation for the COL003 column:
1 byte for the left parenthesis
+ I byte for the single quote
+ 10 to 20 bytes for the first element
+ 1 byte for the single quote
+ 1 byte for the comma
+ 1 byte for the single quote
+ 10 to 20 bytes for the second element
+ 1 byte for the single quote
+ 1 byte for the right parenthesis
---------
47 bytes
Here are 2 sample data for the COL003 column:
Sample data 1: ('3105551234','3105551234')
Sample data 2: ('''''''''''''''''''''','''''''''''''''''''''')
Sample data 1 contains 2 elements of phone numbers.Sample data 2 contains 2 elements of all single quote characters.
In this example, the COL004 column is defined as VARCHAR(17), because it is the maximum representation for the COL004 column in the table.
Here is the calculation for the maximum representation for the COL004 column:
1 byte for the left parenthesis
+ 1 to 7 bytes for the first element
+ 1 byte for the comma
+ 1 to 7 bytes for the second element
+ byte for the right parenthesis
---------
17 bytes
Here are 2 sample data for the COL004 column:
Sample data 1: (-123.45,888.10) Sample data 2: (+123.45,-888.10)
In this example, the COL005 column is defined as VARCHAR(25), because it is the maximum representation for the COL005 column in the table.
Here is the calculation for the maximum representation for the COL005 column:
1 byte for the left parenthesis
+ 1 to 11 bytes for the first element
+ byte for the comma
+ 1 to 11 bytes for the first element
+ 1 byte for the right parenthesis
---------
25 bytes
Here are 2 sample data for the COL005 column:
Sample data 1: (-2147483648,+2147483647) Sample data 2: (0,0)
Use the Teradata SQL HELP TYPE statement to determine the maximum length for the ARRAY data type, as given by the value returned by MaxLength.
For more information about the external representations for the ARRAY data type, see “External Representation for UDTs" in Teradata Vantage™ - Data Types and Literals, B035-1143.