org.apache.paimon.schema

Class SchemaMergingUtils

java.lang.Object

org.apache.paimon.schema.SchemaMergingUtils

public class SchemaMergingUtils
extends Object

The util class for merging the schemas.

Constructor Summary

Constructors

Constructor and Description
SchemaMergingUtils()

Method Summary

Modifier and Type	Method and Description
static DataType	merge(DataType base0, DataType update0, AtomicInteger highestFieldId, boolean allowExplicitCast) Merge the base data type and the update data type if possible.
static RowType	mergeSchemas(RowType tableSchema, RowType dataSchema, AtomicInteger highestFieldId, boolean allowExplicitCast)
static TableSchema	mergeSchemas(TableSchema currentTableSchema, RowType targetType, boolean allowExplicitCast)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SchemaMergingUtils

public SchemaMergingUtils()

Method Detail

mergeSchemas

public static TableSchema mergeSchemas(TableSchema currentTableSchema,
                                       RowType targetType,
                                       boolean allowExplicitCast)

mergeSchemas

public static RowType mergeSchemas(RowType tableSchema,
                                   RowType dataSchema,
                                   AtomicInteger highestFieldId,
                                   boolean allowExplicitCast)

merge

public static DataType merge(DataType base0,
                             DataType update0,
                             AtomicInteger highestFieldId,
                             boolean allowExplicitCast)

Merge the base data type and the update data type if possible.

For RowType, find the fields which exists in both the base schema and the update schema, and try to merge them by calling the method iteratively; remain those fields that are only in the base schema and append those fields that are only in the update schema.

For other complex type, try to merge the element types.

For primitive data type, we treat that's compatible if the original type can be safely cast to the new type.