case-insensitive index lower()

On Tue, Dec 20, 2016 at 10:02:42AM +0000, loren.szendre@gmail.com wrote:

The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/9.1/static/sql-createindex.html
Description:

In the section on indexes the documentation accurately describes how to
create an efficient, case-insensitive index using lower(field_name). But! in
Firebird to get a query to utilize such index, you must write the query as
such:

WHERE myfield = lower(:myfield)

Otherwise a table scan is performed. The documentation should state whether
or not such a thing is required. It's one thing to create an index, it's
quite another to know how to write a statement that guarantees that the
index will be used.

I don't see that as useful for the majority of people reading the
documentation. EXPLAIN will clearly show the index being used.

--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ As you are, so once was I.  As I am, so you will be. +
+                      Ancient Roman grave inscription +

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