liquibase-core/src/main/java/liquibase/database/core/HsqlDatabase.java
public static boolean supportsDefaultValueComputed(String columnType, String defaultValue) {
        HashSet<String> possibleComputedValues = SUPPORTED_DEFAULT_VALUE_COMPUTED_MAP.get(columnType);
        return (possibleComputedValues != null) && possibleComputedValues.contains(defaultValue.toLowerCase());
    }
public static boolean supportsDefaultValueComputed(String columnType, String defaultValue) {
        HashSet<String> possibleComputedValues = SUPPORTED_DEFAULT_VALUE_COMPUTED_MAP.get(columnType);
        return (possibleComputedValues != null) && possibleComputedValues.contains(defaultValue.toLowerCase());
    }
Checks to see if the string is an acceptable computed value for HSQL
"datetime" columns are the only columns for which HSQL supports computer values.

@param columnType   String of the column's data type
@param defaultValue String to be checked for valid valueComputed in HSQL
@return boolean True if the string represents a function supported by HSQL for default values