Hello

I write about the documentation of full-text search.

Section

12.2.2. Creating Indexes
https://www.postgresql.org/docs/current/textsearch-tables.html#TEXTSEARCH-TABLES-INDEX

wrtites the following: "Another approach is to create a separate tsvector 
column to hold the output of to_tsvector. To keep this column automatically up 
to date with its source data, use a stored generated column. This example is a 
concatenation of title and body, using coalesce to ensure that one field will 
still be indexed when the other is NULL"

Section

12.4.3. Triggers for Automatic Updates
https://www.postgresql.org/docs/current/textsearch-features.html#TEXTSEARCH-UPDATE-TRIGGERS

writes the following: "When using a separate column to store the tsvector 
representation of your documents, it is necessary to create a trigger to update 
the tsvector column when the document content columns change. Two built-in 
trigger functions are available for this, or you can write your own."

Thus, one part of the documentation states that one should use the generated 
column-based approach and another part states that one should use the 
trigger-based approach to keep the values in a tsvector column up-to-date. If 
these solutions are both appropriate, then the documentation should state this.

Perhaps something like that?

"Another approach is to create a separate tsvector column to hold the output of 
to_tsvector. It is possible to use a stored generated column to keep this 
column automatically up to date with its source data. This example is a 
concatenation of title and body, using coalesce to ensure that one field will 
still be indexed when the other is NULL"

writes the following: "When using a separate column to store the tsvector 
representation of your documents the column has to be kept up to date with its 
source data. It is possible to create a trigger to update the tsvector column 
when the document content columns change. Two built-in trigger functions are 
available for this, or you can write your own."

Best regards
Erki Eessaar

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