This documentation is for an unreleased version of Apache Paimon. We recommend you use the latest stable version.
File Index
File index #
Define file-index.${index_type}.columns, Paimon will create its corresponding index file for each file. If the index
file is too small, it will be stored directly in the manifest, or in the directory of the data file. Each data file
corresponds to an index file, which has a separate file definition and can contain different types of indexes with
multiple columns.
Index File #
File index file format. Put all column and offset in the header.
_____________________________________ _____________________ ｜ magic ｜version｜head length ｜ ｜-------------------------------------｜ ｜ column number ｜ ｜-------------------------------------｜ ｜ column 1 ｜ index number ｜ ｜-------------------------------------｜ ｜ index name 1 ｜start pos ｜length ｜ ｜-------------------------------------｜ ｜ index name 2 ｜start pos ｜length ｜ ｜-------------------------------------｜ ｜ index name 3 ｜start pos ｜length ｜ ｜-------------------------------------｜ HEAD ｜ column 2 ｜ index number ｜ ｜-------------------------------------｜ ｜ index name 1 ｜start pos ｜length ｜ ｜-------------------------------------｜ ｜ index name 2 ｜start pos ｜length ｜ ｜-------------------------------------｜ ｜ index name 3 ｜start pos ｜length ｜ ｜-------------------------------------｜ ｜ ... ｜ ｜-------------------------------------｜ ｜ ... ｜ ｜-------------------------------------｜ ｜ redundant length ｜redundant bytes ｜ ｜-------------------------------------｜ --------------------- ｜ BODY ｜ ｜ BODY ｜ ｜ BODY ｜ BODY ｜ BODY ｜ ｜_____________________________________｜ _____________________ * magic: 8 bytes long, value is 1493475289347502L, BIT_ENDIAN version: 4 bytes int, BIT_ENDIAN head length: 4 bytes int, BIT_ENDIAN column number: 4 bytes int, BIT_ENDIAN column x name: 2 bytes short BIT_ENDIAN and Java modified-utf-8 index number: 4 bytes int (how many column items below), BIT_ENDIAN index name x: 2 bytes short BIT_ENDIAN and Java modified-utf-8 start pos: 4 bytes int, BIT_ENDIAN length: 4 bytes int, BIT_ENDIAN redundant length: 4 bytes int (for compatibility with later versions, in this version, content is zero) redundant bytes: var bytes (for compatibility with later version, in this version, is empty) BODY: column index bytes + column index bytes + column index bytes + .......
Column Index Bytes: BloomFilter #
Define 'file-index.bloom-filter.columns'.
Content of bloom filter index is simple:
- numHashFunctions 4 bytes int, BIT_ENDIAN
- bloom filter bytes
This class use (64-bits) long hash. Store the num hash function (one integer) and bit set bytes only. Hash bytes type (like varchar, binary, etc.) using xx hash, hash numeric type by specified number hash.
Column Index Bytes: Bitmap #
Define 'file-index.bitmap.columns'.
Bitmap file index format (V1):
Bitmap file index format (V1)
+-------------------------------------------------+-----------------
｜ version (1 byte) ｜
+-------------------------------------------------+
｜ row count (4 bytes int) ｜
+-------------------------------------------------+
｜ non-null value bitmap number (4 bytes int) ｜
+-------------------------------------------------+
｜ has null value (1 byte) ｜
+-------------------------------------------------+
｜ null value offset (4 bytes if has null value) ｜ HEAD
+-------------------------------------------------+
｜ value 1 | offset 1 ｜
+-------------------------------------------------+
｜ value 2 | offset 2 ｜
+-------------------------------------------------+
｜ value 3 | offset 3 ｜
+-------------------------------------------------+
｜ ... ｜
+-------------------------------------------------+-----------------
｜ serialized bitmap 1 ｜
+-------------------------------------------------+
｜ serialized bitmap 2 ｜
+-------------------------------------------------+ BODY
｜ serialized bitmap 3 ｜
+-------------------------------------------------+
｜ ... ｜
+-------------------------------------------------+-----------------
*
value x: var bytes for any data type (as bitmap identifier)
offset: 4 bytes int (when it is negative, it represents that there is only one value
and its position is the inverse of the negative value)
Integer are all BIT_ENDIAN.