[FLINK-11951] Enhance UserDefinedFunction interface to allow more user defined types

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Invalid
• Component/s: Table SQL / API
• Labels: pull-request-available
• Assignee: Jingsong Lee
• Reporter: Jingsong Lee
• Created: 18/Mar/19 09:21
• Updated: 20/Dec/19 08:59
• Resolved: 20/Dec/19 08:59

Description

1.Allow UDF & UDTF to access constant parameter values at getReturnType, see similar feature in hive: https://hive.apache.org/javadocs/r2.2.0/api/org/apache/hadoop/hive/ql/udf/generic/GenericUDF.html#initializeAndFoldConstants-org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector:A-

/**
 * The input arguments are the input arguments which are passed to the eval() method.
 * Only the literal arguments (constant values) are passed to the [[getResultType()]] method.
 * If non-literal arguments appear, it will pass nulls instead.
 *
 * @param arguments arguments of a function call (only literal arguments
 *                  are passed, nulls for non-literal ones)
 * @param argTypes The classes of the arguments of the called eval() method.
 * @return TypeInformation of result type or null if Flink should determine the type
 */
public TypeInformation<?> getResultType(Object[] arguments, Class<?>[] argTypes)

2.Allow AggregateFunction to decide its user define inputs types with argClasses.

/**
 * Returns the result type of the user defined inputs with a given signature.
 */
public TypeInformation[] getUserDefinedInputTypes(Class[] argTypes)

Issue Links

• is a child of: FLINK-11492 Support the full Blink SQL runtime
• links to: GitHub Pull Request #8003