executor

Documentation

Index

• Variables
• type DataStorageScanner
  • func NewKVBasedDataStorageScanner(kv storage.KVStorage) DataStorageScanner
• type ScanOption
  • func WithScanBuffer(buffer *buf.ByteBuf) ScanOption
  • func WithScanBytesLimit(value uint64) ScanOption
  • func WithScanCountLimit(value uint64) ScanOption
  • func WithScanEndKey(endKey []byte) ScanOption
  • func WithScanFilterFunc(filterFunc func([]byte) bool) ScanOption
  • func WithScanStartKey(startKey []byte) ScanOption
  • func WithValue() ScanOption
• type ScanStartKeyPolicy

Variables

var (
	// None no need to next scan
	None = ScanStartKeyPolicy(0)
	// GenWithResultLastKey use `kv.NextKey(last result key)` as startKey for next scan
	GenWithResultLastKey = ScanStartKeyPolicy(1)
	// UseShardEnd use the endKey of the shard as startKey for next scan
	UseShardEnd = ScanStartKeyPolicy(2)
)

Types

type DataStorageScanner

type DataStorageScanner interface {
	// Scan Scan the data in the specified shard to satisfy the conditions,
	// the qualifying conditions can be specified using options.
	//
	// When a key satisfies the condition, the handler will be called.
	// The key and value passed to the handler are not safe and will be reused
	// between multiple handler calls, and need to be copied if they need to be saved.
	//
	// completed to true means that the scan is completed in all shards, otherwise the
	// client needs nextKeyPolicy to create the startKey for the next scan.
	Scan(shard meta.Shard, handler func(key, value []byte) error, options ...ScanOption) (completed bool, nextKeyPolicy ScanStartKeyPolicy, err error)
}

DataStorageScanner

func NewKVBasedDataStorageScanner

func NewKVBasedDataStorageScanner(kv storage.KVStorage) DataStorageScanner

NewKVBasedDataStorageScanner create a kv based DataStorageScanner

type ScanOption

type ScanOption func(*scanOptions)

ScanOption scan option func

func WithScanBuffer

func WithScanBuffer(buffer *buf.ByteBuf) ScanOption

WithScanBuffer set the buffer of scan to avoid memory overhead

func WithScanBytesLimit

func WithScanBytesLimit(value uint64) ScanOption

WithScanBytesLimit set the maximum number of bytes of data to be included in the result

func WithScanCountLimit

func WithScanCountLimit(value uint64) ScanOption

WithScanCountLimit set the maximum number of data to be included in the result

func WithScanEndKey

func WithScanEndKey(endKey []byte) ScanOption

WithScanEndKey set the endKey of scan

func WithScanFilterFunc

func WithScanFilterFunc(filterFunc func([]byte) bool) ScanOption

WithScanFilterFunc set the key filter and return true to indicate that the record meets the condition

func WithScanStartKey

func WithScanStartKey(startKey []byte) ScanOption

WithScanStartKey set the startKey of scan

func WithValue

func WithValue() ScanOption

WithValue set whether the return result of scan contains value

type ScanStartKeyPolicy

type ScanStartKeyPolicy int

ScanStartKeyPolicy calculation strategy for the startKey of next scan