Pseudo-columns

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A pseudo-column is an expression that you can use in the SELECT list of a SQL statement as if it were a column name, but that does not refer to a physical column in a table.

You can use pseudo-columns in SELECT output lists but also as the value of certain attributes in USoft Definer, in particular, in the Default Value attribute of Columns and Domains.

Pseudo-column

Description

ROWNUM

The sequence number of a given record in a query result set

USER

The name of the USoft application user currently logged in.

$$USER$$

The name of the USoft application user currently logged in.

$$RDBMSUSER$$

The name of the user used to access the RDBMS resources.

$$RDBMSOWNER$$

The name of the user who owns the RDBMS objects being accessed.

$$CURRENTDATE$$

The current server date.

$$CURRENTDATETIME$$

The current server date and time.

SYSDATE

The current server date.*

$$TRANSACTIONDATETIME$$

The server date and time of the first time this function is processed within the transaction.

* SYSDATE is Oracle-only. For portability to other platforms, use $$CURRENTDATE$$ or the CURRENT_DATE SQL function instead.

Notes

Pseudo-columns are similar to SQL functions that take no arguments, such as TRANSACTION_DATE(). They differ from such functions in that the call syntax does not use empty parentheses ():

SELECT    USER

SELECT    $$USER$$

SELECT    TRANSACTION_DATE()

 

Another difference is that you can use a pseudo-column, but not a SQL function, as the Default Value attribute of a Column or Domain.

 

See also

Column expressions

Host variables in SQL

SQL conditions

SQL and the Rules Engine