Variables embedded in function-string input or output templates are symbolic markers for various runtime values.
A variable can represent a column name, the name of a system-defined variable, the name of a parameter in a user-defined function, or a user-defined variable defined in an input template. The variable must refer to a value with the same datatype as anything to which it is assigned.
Function-string variables are enclosed inside of a pair of question marks (?), as shown:
?variable!modifier?
The modifier portion of a variable identifies the type of data the variable represents. The modifier is separated from the variable name with an exclamation (!).
The rs_truncate function string accepts position-based function string variable in the format:
?n!param?
Where n is a number from 1 to 255, representing
the position of function parameter in the LTL. The first parameter
for rs_truncate in the LTL is represented
in function string as ?1!param?.
For position based function string variable, the only acceptable
modifier is param.
A sample function string for rs_truncate with the position-based variable is as follows:
truncate table publishers partition ?1!param?
Replication Server recognizes the modifiers listed in Table 2-3:
Modifier |
Description |
|---|---|
new, new_raw |
A reference to the new value of a column in a row that Replication Server is inserting or updating. |
old, old_raw |
A reference to the old values of a column in a row that Replication Server is inserting or updating. |
user, user_raw |
A reference to a variable that is defined in the input template of an rs_select or rs_select_with_lock function string. |
sys, sys_raw |
A reference to a system-defined variable. |
param, param_raw |
A reference to a stored-procedure parameter. |
text_status |
A reference to the text_status value for text, unitext, or image data. Possible values are:
|
Function strings for user-defined functions may not
use the new or old modifiers.
Refer to Chapter 3, “Replication Server Commands,” in the Replication Server Reference Manual for a list of system-defined variables that you can use in function-string input or output templates.
See “Using the default system variable” for information on applications for that system variable.
