tantivy-bitpacker

Tantivy 0.10.0 index format is compatible with the index format in 0.9.0.

• Added an API to easily tweak or entirely replace the default score. See TopDocs::tweak_scoreand TopScore::custom_score (@fulmicoton)
• Added an ASCII folding filter (@drusellers)
• Bugfix in query.count in presence of deletes (@fulmicoton)
• Added .explain(...) in Query and Weight to (@fulmicoton)
• Added an efficient way to delete_all_documents in IndexWriter (@petr-tik). All segments are simply removed.

Minor

• Switched to Rust 2018 (@uvd)
• Small simplification of the code. Calling .freq() or .doc() when .advance() has never been called on segment postings should panic from now on.
• Tokens exceeding u16::max_value() - 4 chars are discarded silently instead of panicking.
• Fast fields are now preloaded when the SegmentReader is created.
• IndexMeta is now public. (@hntd187)
• IndexWriter add_document, delete_term. IndexWriter is Sync, making it possible to use it with a Arc<RwLock<IndexWriter>>. add_document and delete_term can only require a read lock. (@fulmicoton)
• Introducing Opstamp as an expressive type alias for u64. (@petr-tik)
• Stamper now relies on AtomicU64 on all platforms (@petr-tik)
• Bugfix - Files get deleted slightly earlier
• Compilation resources improved (@fdb-hiroshima)

How to update?

Your program should be usable as is.

Fast fields

Fast fields used to be accessed directly from the SegmentReader. The API changed, you are now required to acquire your fast field reader via the segment_reader.fast_fields(), and use one of the typed method:

• .u64(), .i64() if your field is single-valued ;
• .u64s(), .i64s() if your field is multi-valued ;
• .bytes() if your field is bytes fast field.

0.9.0 index format is not compatible with the previous index format.

• MAJOR BUGFIX : Some Mmap objects were being leaked, and would never get released. (@fulmicoton)
• Removed most unsafe (@fulmicoton)
• Indexer memory footprint improved. (VInt comp, inlining the first block. (@fulmicoton)
• Stemming in other language possible (@pentlander)
• Segments with no docs are deleted earlier (@barrotsteindev)
• Added grouped add and delete operations. They are guaranteed to happen together (i.e. they cannot be split by a commit). In addition, adds are guaranteed to happen on the same segment. (@elbow-jason)
• Removed INT_STORED and INT_INDEXED. It is now possible to use STORED and INDEXED for int fields. (@fulmicoton)
• Added DateTime field (@barrotsteindev)
• Added IndexReader. By default, index is reloaded automatically upon new commits (@fulmicoton)
• SIMD linear search within blocks (@fulmicoton)

How to update ?

tantivy 0.9 brought some API breaking change. To update from tantivy 0.8, you will need to go through the following steps.

• schema::INT_INDEXED and schema::INT_STORED should be replaced by schema::INDEXED and schema::INT_STORED.

• The index now does not hold the pool of searcher anymore. You are required to create an intermediary object called IndexReader for this.

  // create the reader. You typically need to create 1 reader for the entire
  // lifetime of you program.
  let reader = index.reader()?;
  
  // Acquire a searcher (previously `index.searcher()`) is now written:
  let searcher = reader.searcher();
  
  // With the default setting of the reader, you are not required to
  // call `index.load_searchers()` anymore.
  //
  // The IndexReader will pick up that change automatically, regardless
  // of whether the update was done in a different process or not.
  // If this behavior is not wanted, you can create your reader with
  // the `ReloadPolicy::Manual`, and manually decide when to reload the index
  // by calling `reader.reload()?`.
  
  

No change in the index format

• API Breaking change in the collector API. (@jwolfe, @fulmicoton)
• Multithreaded search (@jwolfe, @fulmicoton)

• Raise the limit of number of fields (previously 256 fields) (@fulmicoton)
• Removed u32 fields. They are replaced by u64 and i64 fields (#65) (@fulmicoton)
• Optimized skip in SegmentPostings (#130) (@lnicola)
• Replacing rustc_serialize by serde. Kudos to benchmark@KodrAus and @lnicola
• Using error-chain (@KodrAus)
• QueryParser: (@fulmicoton)
  • Explicit error returned when searched for a term that is not indexed
  • Searching for a int term via the query parser was broken (age:1)
  • Searching for a non-indexed field returns an explicit Error
  • Phrase query for non-tokenized field are not tokenized by the query parser.
• Faster/Better indexing (@fulmicoton)
  • using murmurhash2
  • faster merging
  • more memory efficient fast field writer (@lnicola )
  • better handling of collisions
  • lesser memory usage
• Added API, most notably to iterate over ranges of terms (@fulmicoton)
• Bugfix that was preventing to unmap segment files, on index drop (@fulmicoton)
• Made the doc! macro public (@fulmicoton)
• Added an alternative implementation of the streaming dictionary (@fulmicoton)