SqlReturnTypeInferenceChain (Apache Calcite API)

java.lang.Object
- org.apache.calcite.sql.type.SqlReturnTypeInferenceChain

All Implemented Interfaces:

SqlReturnTypeInference
```
public class SqlReturnTypeInferenceChain
extends java.lang.Object
implements SqlReturnTypeInference
```
Strategy to infer the type of an operator call from the type of the operands by using a series of SqlReturnTypeInference rules in a given order. If a rule fails to find a return type (by returning NULL), next rule is tried until there are no more rules in which case NULL will be returned.

Field Summary

Fields
Modifier and Type Field Description

private com.google.common.collect.ImmutableList<SqlReturnTypeInference> rules

Constructor Summary

Constructors
Constructor Description

SqlReturnTypeInferenceChain(SqlReturnTypeInference... rules)
Creates a SqlReturnTypeInferenceChain from an array of rules.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`RelDataType`	`inferReturnType(SqlOperatorBinding opBinding)`	Infers the return type of a call to an `SqlOperator`.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - rules
```
private final com.google.common.collect.ImmutableList<SqlReturnTypeInference> rules
```
- Constructor Detail
  - SqlReturnTypeInferenceChain
```
SqlReturnTypeInferenceChain(SqlReturnTypeInference... rules)
```
    Creates a SqlReturnTypeInferenceChain from an array of rules.
    Package-protected. Use ReturnTypes.chain(org.apache.calcite.sql.type.SqlReturnTypeInference...).
- Method Detail
  - inferReturnType
```
public RelDataType inferReturnType(SqlOperatorBinding opBinding)
```
    Description copied from interface: SqlReturnTypeInference
    
    Infers the return type of a call to an SqlOperator.
    
    Specified by:
    
    inferReturnType in interface SqlReturnTypeInference
    
    Parameters:
    
    opBinding - description of operator binding
    
    Returns:
    
    inferred type; may be null