Struct LastFieldsBuilder 

struct LastFieldsBuilder {
    filter_deleted: bool,
    builders: Vec<Box<dyn MutableVector>>,
    last_fields: Vec<Value>,
    contains_null: bool,
    contains_deletion: bool,
    initialized: bool,
}

Buffer to store fields in the last row to merge.

Usage: We should call maybe_init() to initialize the builder and then call push_first_row() to push the first row of batches that the timestamp is the same as the row in this builder. Finally we should call merge_last_non_null() to merge the last non-null fields and return the merged batch.

Fields

filter_deleted: bool

Filter deleted rows.

builders: Vec<Box<dyn MutableVector>>

Fields builders, lazy initialized.

last_fields: Vec<Value>

Last fields to merge, lazy initialized. Only initializes this field when skip_merge() is false.

contains_null: bool

Whether the last row (including last_fields) has null field. Only sets this field when contains_deletion is false.

contains_deletion: bool

Whether the last row has delete op. If true, skips merging fields.

initialized: bool

Whether the builder is initialized.

Implementations

impl LastFieldsBuilder

fn new(filter_deleted: bool) -> Self

Returns a new builder with the given filter_deleted flag.

fn maybe_init(&mut self, batch: &Batch)

Initializes the builders with the last row of the batch.

fn skip_merge(&self) -> bool

Returns true if the builder don’t need to merge the rows.

fn push_first_row(&mut self, batch: &Batch)

Pushes first row of a batch to the builder.

fn merge_last_non_null( &mut self, buffer: Batch, metrics: &mut DedupMetrics, ) -> Result<Option<Batch>>

Merges last non-null fields, builds a new batch and resets the builder. It may overwrites the last row of the buffer. The buffer is the batch that initialized the builder.

fn clear(&mut self)

Clears the builder.