The underlying data in the JSON column is returned without any additional decoding. Path elements can be integers to access values in JSON arrays: from(post in Post, select: ta)Īny element of the path can be dynamic: field = "name"įrom(post in Post, select: ta) Warning The query can be also rewritten as: from(post in Post, select: ta) from(post in Post, select: json_extract_path(ta, )) Returns value from the json_field pointed to by path. To check if a given value is not nil use: from p in Post, where: not is_nil(p.published_at) json_extract_path(json_field, path) from p in Post, where: is_nil(p.published_at) from p in Payment, select: filter(avg(p.value), p.value > 0 and p.value filter(p.value ^since)Ĭhecks if the given value is nil. This is currently only supported by Postgres. filter(value, filter)Īpplies the given expression as a FILTER clause against an aggregate. In the example above, both at_least_four(:doors) and at_least_four(:tires) would be valid calls as the field is dynamically generated. field(source, field)Īllows a field to be dynamically accessed. In the above example the query returns posts which have at least one comment that has more than 5 replies. This is best used in conjunction with parent_as to correlate the subquery with the parent query to test some condition on related rows in a different table. from p in Post, as: :post, where: exists(from(c in Comment, where: parent_as(:post).id = c.post_id and c.replies_count > 5, select: 1)) exists(subquery)Įvaluates to true if the provided subquery returns 1 or more rows. See Intervals for supported interval values. If you want to perform operations on date, date_add/3 could be used. In the example above, we used datetime_add/3 to subtract one month from the current datetime and compared it with the p.published_at. The first argument is a datetime, the second one is the count for the interval, which may be either positive or negative and the interval value: # Get all items published since the last monthĭatetime_add(^NaiveDateTime.utc_now(), -1, "month") from p in Post, select: count(p.id, :distinct) date_add(date, count, interval) from p in Post, select: count(p.id) count(value, atom)Ĭounts the distinct values in given entry. from p in Post, select: count() count(value)Ĭounts the given entry. Both can be used with every comparison operator: =, !=, >, >=, coalesce(p.backup_value) |> coalesce(0) count()Ĭounts the entries in the table. Both can be used with every comparison operator: =, !=, >, >=, ^since and li.qty >= 10)Ī product matches in the above example if a line item was created since the provided date where the customer purchased at least 10 units.īoth any and all must be given a subquery as an argument, and theyu must be used on the right hand side of a comparison. The above example matches all the posts which are tied for being the most visited.īoth any and all must be given a subquery as an argument, and theyu must be used on the right hand side of a comparison. from p in Post, where: p.visits >= all(įrom(p in Post, select: avg(p.visits), group_by: )įor a post to match in the above example it must be visited at least as much as the average post in all categories. Examples from p in Post, where: p.published_at > ago(3, "month") all(subquery)Įvaluates whether all values returned from the provided subquery match in a comparison operation. The current time in UTC is retrieved from Elixir and not from the database. Subtracts the given interval from the current time in UTC. So if your adapter allows you to use them in a certain way (like adding a date and an interval in PostgreSQL), it should work just fine in Ecto queries. The Ecto implementation of these operators provide only a thin layer above the adapters. Window APIĮcto also supports many of the windows functions found in SQL databases. IntervalsĮcto supports following values for interval option: "year", "month", "week", "day", "hour", "minute", "second", "millisecond", and "microsecond".ĭate/ Time functions like datetime_add/3, date_add/3, from_now/2, ago/2 take interval as an argument. Furthermore, it is possible to define your own macros and use them in Ecto queries (see docs for fragment/1). Note the functions in this module exist for documentation purposes and one should never need to invoke them directly. General: fragment/1, field/2, type/2, as/1, parent_as/1. Inside select: struct/2, map/2, merge/2 and literals (map, tuples, lists, etc).Date/time intervals: datetime_add/3, date_add/3, from_now/2, ago/2.Subquery operators: any, all and exists.Lists all functions allowed in the query API.
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