Struct tikv::coprocessor::statistics::analyze::SampleBuilder

[+] Show declaration

struct SampleBuilder<S: Snapshot> {
    data: BatchTableScanExecutor<TiKVStorage<SnapshotStore<S>>>,
    max_bucket_size: usize,
    max_sample_size: usize,
    max_fm_sketch_size: usize,
    cm_sketch_depth: usize,
    cm_sketch_width: usize,
    stats_version: i32,
    top_n_size: usize,
    columns_info: Vec<ColumnInfo>,
    analyze_common_handle: bool,
    common_handle_col_ids: Vec<i64>,
}

Fields

data: BatchTableScanExecutor<TiKVStorage<SnapshotStore<S>>>

max_bucket_size: usize

max_sample_size: usize

max_fm_sketch_size: usize

cm_sketch_depth: usize

cm_sketch_width: usize

stats_version: i32

top_n_size: usize

columns_info: Vec<ColumnInfo>

analyze_common_handle: bool

common_handle_col_ids: Vec<i64>

Implementations

impl<S: Snapshot> SampleBuilder<S>[−]

[−] Expand description

SampleBuilder is used to analyze columns. It collects sample from the result set using Reservoir Sampling algorithm, estimates NDVs using FM Sketch during the collecting process, and builds count-min sketch.

fn new(
    req: AnalyzeColumnsReq,
    common_handle_req: Option<AnalyzeIndexReq>,
    storage: TiKVStorage<SnapshotStore<S>>,
    ranges: Vec<KeyRange>
) -> Result<Self>

async fn collect_columns_stats(
    &mut self
) -> Result<(AnalyzeColumnsResult, Option<AnalyzeIndexResult>)>