Interface QueryProvider

Provides query capability for one or more data/FeatureSource!FeatureSources.

interface QueryProvider {
    count(source: FeatureSource, where: string, options?: QueryOptions): Promise<CountResult>;
    isSupported(source: FeatureSource): boolean;
    query(source: FeatureSource | FeatureSource[], where: string, options?: QueryOptions): AsyncIterable<Feature, any, any>;
}

Implemented by

QueryProviderBase

Index

Methods

count isSupported query

Methods

count

count(source, where, options?): Promise<CountResult>
Queries a given feature source for a count of features that match the query criteria.
Parameters
- source: FeatureSource
  The source to query.
- where: string
  An SQL expression to match against, e.g. "lastName='Smith'".
- Optionaloptions: QueryOptions
  Additional options that affect the query.
Returns Promise<CountResult>

isSupported

isSupported(source): boolean
Determines whether this provider can handle queries for the given feature source.
Parameters
- source: FeatureSource
  The feature source.
Returns boolean

query

query(source, where, options?): AsyncIterable<Feature, any, any>
Queries a given feature source for features that match the query criteria.
Parameters
- source: FeatureSource | FeatureSource[]
  The source to query.
- where: string
  An SQL expression to match against, e.g. "lastName='Smith'".
- Optionaloptions: QueryOptions
  Additional options that affect the query.
Returns AsyncIterable<Feature, any, any>