Earth Engine is introducingnoncommercial quota tiersto safeguard shared compute resources and ensure reliable performance for everyone. All noncommercial projects will need to select a quota tier byApril 27, 2026or will use the Community Tier by default. Tier quotas will take effect for all projects (regardless of tier selection date) onApril 27, 2026.Learn more.
Join OverviewStay organized with collectionsSave and categorize content based on your preferences.
Joins are used to combine elements from different collections (e.g.ImageCollectionorFeatureCollection) based on a condition
specified by anee.Filter. The filter is constructed with arguments for
the properties in each collection that are related to each other. Specifically,leftFieldspecifies the property in the primary collection that is related
to therightFieldin the secondary collection. The type of filter (e.g.equals,greaterThanOrEquals,lessThan, etc.)
indicates the relationship between the fields. The type of join indicates one-to-many
or one-to-one relationships between the elements in the collections and how many matches
to retain. The output of a join is produced byjoin.apply()and will vary
according to the type of join.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2021-05-26 UTC."],[],["Joins combine elements from different collections using an `ee.Filter` based on a specified condition. `leftField` and `rightField` define related properties within the primary and secondary collections, respectively. The filter type determines the relationship between these fields (e.g., equals, greaterThan). Join type specifies one-to-many or one-to-one relationships and the number of matches. The `join.apply()` method produces the output, which varies based on the chosen join type.\n"]]
