public String toSQL (String functionName, Collection parameters, ISQLBuilderHelper helper) throws Exception
This method must return the SQL representation of the function if it supports one. The SQL representation is essential if a function is to be used in queries. If the SQL representation is not provided it will not be possible to use the function in queries. See also an example later in this section.
functionName | the name of the function in the library that needs to be represented in the SQL form. |
parameters | parameters of the function specified as a collection of the IArithmeticNode objects. To get an SQL representation of a parameter use the toSQL method of the IArithmeticNode interface. |
helper | a call-back interface that contains certain methods that may help define the SQL representation. See the ISQLBuilderHelper interface. |
A string representing the SQL expression that calculates the function value.
UnsupportedSQLElementException if the SQL representation for the function is not supported.