Average - Paradedb — ContextQMD

The following query computes the average value over a specific field:

<CodeGroup> ```sql SQL SELECT pdb.agg('{"avg": {"field": "rating"}}') FROM mock_items WHERE id @@@ pdb.all(); ```

import { search } from "@paradedb/drizzle-paradedb";

await db
  .select({
    agg: search.agg({ avg: { field: "rating" } }),
  })
  .from(mockItems)
  .where(search.all(mockItems.id));

python

from paradedb import Agg, All, ParadeDB

MockItem.objects.filter(
    id=ParadeDB(All())
).aggregate(agg=Agg('{"avg": {"field": "rating"}}'))

python

from sqlalchemy import select
from sqlalchemy.orm import Session
from paradedb.sqlalchemy import facets, pdb, search

stmt = (
    select(pdb.agg(facets.avg(field="rating")))
    .select_from(MockItem)
    .where(search.all(MockItem.id))
)

with Session(engine) as session:
    session.execute(stmt).all()

ruby

MockItem.search(:id)
        .match_all
        .facets_agg(agg: ParadeDB::Aggregations.avg(:rating))

await dbContext
    .MockItems.Where(item => EF.Functions.All(item.Id))
    .Select(item => EF.Functions.Agg(new { avg = new { field = "rating" } }))
    .ToListAsync();

</CodeGroup>

ini

              agg
-------------------------------
 {"value": 3.8536585365853657}
(1 row)

See the Tantivy documentation for all available options.

SQL Average Syntax

SQL's AVERAGE syntax is supported in beta. To enable it, first run

sql

SET paradedb.enable_aggregate_custom_scan TO on;

With this feature enabled, the following query is equivalent to the above and is executed in the same way.

sql

SELECT AVG(rating) FROM mock_items
WHERE id @@@ pdb.all();

By default, AVG ignores null values. Use COALESCE to include them in the final average:

sql

SELECT AVG(COALESCE(rating, 0)) FROM mock_items
WHERE id @@@ pdb.all();