## postgresql – Avoid sorting on the group indexed by caused by DATE_TRUNC

Is there a way to avoid `Sort` operation for `GROUP BY`, caused by the `DATE_TRUNC` function not recognized as `tstamp`, which is part of `ix` index? This function does not really affect the order maintained by the `ix`.

``````CREATE INDEX ix ON tbl(col, tstamp, num)

SELECT col,
DATE_TRUNC('MONTH', tstamp AT TIME ZONE 'UTC') AS trunc,
SUM(num)
FROM tbl
WHERE col IN (?, ?, ...)
AND tstamp >= ?
AND tstamp <  ?
GROUP BY col, trunc
``````

Precision setting for `DATE_TRUNC` is dynamic it could also be `'DAY'` or `'YEAR'`... so I cannot index this function without creating an index for each variation.

The execution plan that I get:

``````Finalize GroupAggregate
Group Key: col, DATE_TRUNC('MONTH', tstamp AT TIME ZONE 'UTC')
->  Gather Merge
Workers Planned: 2
Workers Launched: 2
->  Partial GroupAggregate
Group Key: col, DATE_TRUNC('MONTH', tstamp AT TIME ZONE 'UTC')
->  Sort
Sort Key: col, DATE_TRUNC('MONTH', tstamp AT TIME ZONE 'UTC')
Sort Method: external merge  Disk: ...kB
-> Parallel Index Only Scan using ix on tbl
Index Cond: ((col = ANY (...)) AND (tstamp >= ...) AND (tstamp < ...))
Heap Fetches: 0
``````

The execution plan I want would look like this:

``````GroupAggregate
Group Key: col, DATE_TRUNC('MONTH', tstamp AT TIME ZONE 'UTC')
->  Index Only Scan using ix on tbl
Index Cond: ((col = ANY (...)) AND (tstamp >= ...) AND (tstamp < ...))
Heap Fetches: 0
``````

(I get it if I don't use it `DATE_TRUNC`)

Google Search Console tells me that my home page has been successfully indexed, but this is the only one. The home page has about 25 internal links, all of them work fine, and none of these appear on the "Cover" tab.

The HTML of the analyzed page (indexed HTML) displays all the links correctly.

Why has it not indexed internal links, if the home page seems to be correctly rendered and indexed by the robot?

I am using javascript to retrieve content via ajax for each link, but that shouldn't be a problem as Google Bot has been able to run js for quite some time now. (right?)

The URL is https://www.canadastepbystep.com, if that helps.

I know I could use sitemaps, but I would like to go "clean" and let the robot do its job.

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I am developing a React application.

Up to now, indexing coverage has been poor (only the home page has been indexed).

I recently implemented server side rendering (SSR) and the indexing coverage seems to be significantly better.

That being said, I feel like I'm playing the SEO game blindly. Is there a way to simulate Googlebot to see what would be indexed? I would love to see the recursive paths that Googlebot sees.

I know Google Search Console, but I can only inspect one URL at a time.

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About two weeks ago, I submitted my sitemap to my site's webmaster https://example.com. Its indexing was successful, but no unique URL was found. It shows 0 now. Three weeks have passed, but nothing has changed. I manually indexed each message.

## Google has successfully indexed my sitemap, but the URLs have been discovered.

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I am trying to impose rules like

``````x[b,c,d]+x[a,c,d]+x[a,b,d]+x[a,b,c]=0
``````

for all distinct integers a, b, c, d to simplify a function consists of `x[a,b,c]`. However, the `Forall` the function doesn't do the job. Is there a way to do this?

Any help would be appreciated: D

## Calculation of an amount indexed by \$ t | gcd (m, n) \$

I would like to know how to implement the sum $$f (m, n) = frac {1} {n} left ( sum_ {t | gcd (m, n)} { frac {m} {t} + frac {n} {t} -1 choose frac {m} {t}} phi (t) right)$$
for two given positive inputs $$m, n$$. Here, $$phi$$ is the totient function of Euler and the thing in parentheses is binomial notation. My difficulty is to define the sum of all packages $${ frac {m} {t} + frac {n} {t} -1 choose frac {m} {t}} phi (t)$$ such as $$t$$ Split $$gcd (m, n)$$. I guess there is a simple solution to this.

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## How to check the number of images indexed in Google?

Hi,

Can someone tell me if there is a way to check the number of images from a site indexed in Google?

Any help would be appreciated.

cordially
WM

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In the product tab of the admin panel, is it possible to increase search and filtering performance? I have a large number of products, and it takes at least 45 seconds minimum to get an answer.

Is it even indexed? I have configured ElasticSearch 5, shouldn't that be at least usable?