duckdb::FSSTPrimitives Class Reference

Classes
struct	StringWithExtraSpace

Static Public Member Functions
static string_t	DecompressValue (void *duckdb_fsst_decoder, VectorStringBuffer &str_buffer, const char *compressed_string, const idx_t compressed_string_len)
static string_t	DecompressInlinedValue (void *duckdb_fsst_decoder, const char *compressed_string, const idx_t compressed_string_len)
static string	DecompressValue (void *duckdb_fsst_decoder, const char *compressed_string, const idx_t compressed_string_len, vector< unsigned char > &decompress_buffer)

Member Function Documentation

DecompressValue() [1/2]

static string_t duckdb::FSSTPrimitives::DecompressValue ( void *  duckdb_fsst_decoder, VectorStringBuffer &  str_buffer, const char *  compressed_string, const idx_t  compressed_string_len  )

inlinestatic

                                                                                                      {
        const auto max_uncompressed_length = compressed_string_len * 8;
        const auto fsst_decoder = static_cast<duckdb_fsst_decoder_t *>(duckdb_fsst_decoder);
        const auto compressed_string_ptr = (const unsigned char *)compressed_string; // NOLINT
        const auto target_ptr = str_buffer.AllocateShrinkableBuffer(max_uncompressed_length);
        const auto decompressed_string_size = duckdb_fsst_decompress(
            fsst_decoder, compressed_string_len, compressed_string_ptr, max_uncompressed_length, target_ptr);
        return str_buffer.FinalizeShrinkableBuffer(target_ptr, max_uncompressed_length, decompressed_string_size);
    }

DecompressInlinedValue()

static string_t duckdb::FSSTPrimitives::DecompressInlinedValue ( void *  duckdb_fsst_decoder, const char *  compressed_string, const idx_t  compressed_string_len  )

inlinestatic

                                                                              {
        const auto fsst_decoder = static_cast<duckdb_fsst_decoder_t *>(duckdb_fsst_decoder);
        const auto compressed_string_ptr = (const unsigned char *)compressed_string; // NOLINT
        StringWithExtraSpace result;
        const auto target_ptr = (unsigned char *)result.str.GetPrefixWriteable(); // NOLINT
        const auto decompressed_string_size =
            duckdb_fsst_decompress(fsst_decoder, compressed_string_len, compressed_string_ptr,
                                   string_t::INLINE_LENGTH + sizeof(StringWithExtraSpace::extra_space), target_ptr);
        if (decompressed_string_size > string_t::INLINE_LENGTH) {
            throw IOException("Corrupt database file: decoded FSST string of >=%llu bytes (should be <=%llu bytes)",
                              decompressed_string_size, string_t::INLINE_LENGTH);
        }
        D_ASSERT(decompressed_string_size <= string_t::INLINE_LENGTH);
        result.str.SetSizeAndFinalize(UnsafeNumericCast<uint32_t>(decompressed_string_size), string_t::INLINE_LENGTH);
        return result.str;
    }

DecompressValue() [2/2]

string duckdb::FSSTPrimitives::DecompressValue ( void *  duckdb_fsst_decoder, const char *  compressed_string, const idx_t  compressed_string_len, vector< unsigned char > &  decompress_buffer  )

static

                                                                                                                    {
    auto compressed_string_ptr = reinterpret_cast<const unsigned char *>(compressed_string);
    auto fsst_decoder = static_cast<duckdb_fsst_decoder_t *>(duckdb_fsst_decoder);
    auto decompressed_string_size = duckdb_fsst_decompress(fsst_decoder, compressed_string_len, compressed_string_ptr,
                                                           decompress_buffer.size(), decompress_buffer.data());
 
    D_ASSERT(!decompress_buffer.empty());
    D_ASSERT(decompressed_string_size <= decompress_buffer.size() - 1);
    return string(char_ptr_cast(decompress_buffer.data()), decompressed_string_size);
}

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The documentation for this class was generated from the following file:

• external/duckdb/duckdb.cpp