DB errors

Are there any other lines of errors before or after that? If so, can you please share?

Nothing more, like this only.

INSERT INTO wp_yoast_seo_meta (object_id, incoming_link_count) VALUES (23200, '0')
Duplicate entry '23200' for key 'object_id'

(I get errors on email. I wrote special plugin))))

I think the source of errors is in the unconditional INSERT ($this->insert)

	public function upsert( array $data, array $where, $format = null, $where_format = null ) {
		$result = $this->insert( $data, $format );

		if ( false === $result ) {
			$result = $this->update( $data, $where, $format, $where_format );
		}

		return $result;
	}

Maybe it’s better to use REPLACE or INSERT IGNORE?

The invisible (for most users) ERROR still remains an ERROR.

@yube Thanks for your provided feedback. Can you please confirm whether the issue persists with the latest Yoast SEO v5.9.3 and WordPress v4.9.1?

If yes, we expect this to be a bug. We’re actively using the bug tracking on our GitHub repository so your best next step would be to create a new issue for our developers at https://github.com/Yoast/wordpress-seo/issues/new. You will need an account to create a new issue. If this is your first bug report, please check out: https://kb.yoast.com/kb/how-to-write-a-good-bug-report/.

Don’t forget to include the URL to this conversation in your bug report.

Can you please confirm whether the issue persists with the latest Yoast SEO v5.9.3 and WordPress v4.9.1?

Yes. Errors can not fail to be, because it is in the algorithm. Look at my post above. Insert causes “Duplicate entry”, and you check this error by if (false === $result).

If yes, we expect this to be a bug.

It’s an error in the algorithm.

so your best next step would be to create

I can simply turn off report about this kind of errors. I think that is enough that I reported the error here and indicated its cause.

Good luck, colleagues!