Discussion: https://postgr.es/m/CAMkU%3D1zxfA8_MGBW6sJMj54p8nPoe4bMb5LoG-rMYZVPq4j08Q%40mail.gmail.com
Author: Jeff Janes
trigram-based index searches for <literal>LIKE</literal>, <literal>ILIKE</literal>,
<literal>~</literal> and <literal>~*</literal> queries. Beginning in
<productname>PostgreSQL</productname> 14, these indexes also support
- the equality operator (simple comparison operators are not supported).
+ the equality operator (inequality operators are not supported).
Note that those indexes may not be as efficient as regular B-tree indexes
for equality operator.
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