@@ -212,30 +212,22 @@ Continuous aggregates consist of:
212212# ## Materialization hypertable
213213
214214Continuous aggregates take raw data from the original hypertable, aggregate it,
215- and store the intermediate state in a materialization hypertable. When you query
216- the continuous aggregate view, the state is returned to you as needed.
215+ and store the aggregated data in a materialization hypertable. When you query
216+ the continuous aggregate view, the aggregated data is returned to you as needed.
217217
218218Using the same temperature example, the materialization table looks like this:
219219
220- |day|location|chunk|avg temperature partial |
220+ |day|location|chunk|avg temperature|
221221|- |- |- |- |
222- |2021 / 01 / 01 |New York|1 |{ 3 , 219 } |
223- |2021 / 01 / 01 |Stockholm|1 |{ 4 , 280 } |
222+ |2021 / 01 / 01 |New York|1 |73 |
223+ |2021 / 01 / 01 |Stockholm|1 |70 |
224224|2021 / 01 / 02 |New York|2 ||
225- |2021 / 01 / 02 |Stockholm|2 |{ 5 , 345 } |
225+ |2021 / 01 / 02 |Stockholm|2 |69 |
226226
227227The materialization table is stored as a Timescale hypertable, to take
228228advantage of the scaling and query optimizations that hypertables offer.
229229Materialization tables contain a column for each group- by clause in the query,
230- a ` chunk` column identifying which chunk in the raw data this entry came from ,
231- and a ` partial aggregate` column for each aggregate in the query.
232-
233- The partial column is used internally to calculate the output. In this example,
234- because the query looks for an average, the partial column contains the number
235- of rows seen, and the sum of all their values . The most important thing to know
236- about partials is that they can be combined to create new partials spanning all
237- of the old partials' rows. This is important if you combine groups that span
238- multiple chunks.
230+ and an ` aggregate` column for each aggregate in the query.
239231
240232For more information, see [materialization hypertables][cagg- mat- hypertables].
241233
@@ -248,13 +240,6 @@ unblocks other transactions, and materializes the aggregates. The first
248240transaction is very quick, and most of the work happens during the second
249241transaction, to ensure that the work does not interfere with other operations.
250242
251- When you query the continuous aggregate view, the materialization engine
252- combines the aggregate partials into a single partial for each time range, and
253- calculates the value that is returned. For example, to compute an average, each
254- partial sum is added up to a total sum, and each partial count is added up to a
255- total count, then the average is computed as the total sum divided by the total
256- count.
257-
258243# ## Invalidation engine
259244
260245Any change to the data in a hypertable could potentially invalidate some
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