Specifies that a user-defined default value is to be inserted in the field when a value is not specified for a column in an INSERT statement.
Syntax
DEFAULT { constant_value | { DATE | TIME | TIMESTAMP } quotestring | INTERVAL [ sign ] quotestring qualifier }
Syntax Elements
- constant_value
- A default value to be inserted when a column in the target table is omitted from the column_list specification of an INSERT statement.
When no DEFAULT phrase is provided, a NULL is inserted into the field for nullable columns, otherwise an error is returned.
A default value can be a keyword or built-in function. For more information on built-in functions, see Teradata Vantage™ - SQL Functions, Expressions, and Predicates, B035-1145.
The following defines the valid keywords and functions:- number – specifies to insert a numeric literal value as the default value
- NULL – specifies to insert a null (for nullable columns) as the default value
- USER – specifies to insert the user name of the current user as the default value
- CURRENT_DATE – specifies to insert the current system date as the default value
- CURRENT_TIME – specifies to insert the current system time as the default value
- CURRENT_TIMESTAMP – specifies to insert the current system date and time as the default value
- DATE
- A date value in ANSI DATE literal format as the insert default.
- TIME
- A time value in ANSI TIME literal format as the insert default.
- TIMESTAMP
- A timestamp value in ANSI TIMESTAMP literal format as the insert default.
- INTERVAL
- An interval value in ANSI INTERVAL format as the insert default.
- quotestring
- A default value represented as a string enclosed in apostrophes.
- sign
- The sign of an interval value.
- qualifier
- One of the following interval time periods:
- YEAR
- YEAR TO MONTH
- MONTH
- DAY
- DAY TO HOUR
- DAY TO MINUTE
- DAY TO SECOND
- HOUR
- HOUR TO MINUTE
- HOUR TO SECOND
- MINUTE
- MINUTE TO SECOND
- SECOND