CACHEREAD
The CACHEREAD function reads the value associated to a cache variable.
This function returns a default value if specified, or an empty value if the cache variable has not been defined, or if it has been deleted prior to making this function invocation. Otherwise, it returns the associated value of the cache variable to the map in text format. The value associated to a internal cache variable can be retrieved with this function for further transformation purposes. Wildcards are not supported in this map rules because there is no good way to return multiple values.
The value associated to a cache variable is a text expression and returns the new value to the map. Empty value skips creating or updating of a cache variable.
- Syntax:
- CACHEREAD (single-text-expression [, single-text-expression])
- Meaning:
- CACHEREAD (variable_name [, default_value])
- Returns:
- A single text item.
Examples
- flowlib->CACHEREAD (“Greeting”)
Returns the current value of custom cache variable, Greeting, to the map if it exists. Otherwise, returns the default value, empty value.
- flowlib->CACHEREAD (“Greeting”, “Hi”)
Returns the current value of custom cache variable, Greeting, to the map if it exists. Otherwise, returns the default value, Hi, to the map.