Joins are used to combine elements from different collections (e.g.
ImageCollection or FeatureCollection) based on a condition
specified by an ee.Filter. The filter is constructed with arguments for
the properties in each collection that are related to each other. Specifically,
leftField specifies the property in the primary collection that is related
to the rightField in 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 by join.apply() and will vary
according to the type of join.
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Join Overview | Google Earth Engine | Google for Developers
Join Overview
[[["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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2021-05-26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 like `ImageCollection` and `FeatureCollection` based on a specified condition using an `ee.Filter`."],["The `ee.Filter` defines the relationship between properties in the collections using `leftField` and `rightField` along with a filter type like `equals` or `lessThan`."],["Different join types handle one-to-one or one-to-many relationships and control the number of matches retained, impacting the output produced by `join.apply()`."]]],["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"]]
Join Overview
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Last updated 2021-05-26 UTC.