Class SimpleOrderableAggregateMethod

java.lang.Object
org.datanucleus.store.rdbms.sql.method.SimpleOrderableAggregateMethod
All Implemented Interfaces:
SQLMethod
Direct Known Subclasses:
MaxFunction, MinFunction
public abstract class SimpleOrderableAggregateMethod extends Object implements SQLMethod
Expression handler to invoke an SQL aggregated function.
  • The expression should be null and will return an AggregateXXXExpression 
    {functionName}({argExpr})
    when processing a result clause
  • If the compilation component is something else then will generate a subquery expression

  • Constructor Details

    • SimpleOrderableAggregateMethod

      public SimpleOrderableAggregateMethod()

  • Method Details

    • getFunctionName

      protected abstract String getFunctionName()

    • getExpression

      public SQLExpression getExpression(SQLStatement stmt, SQLExpression expr, List<SQLExpression> args)
      Description copied from interface: SQLMethod
      Return the expression for this SQL function.
      Specified by:
      getExpression in interface SQLMethod
      Parameters:
      stmt - SQLStatement that this expression is for
      expr - The expression that it is invoked on
      args - Arguments passed in
      Returns:
      The SQL expression using the SQL function