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From: Ron <ronljohnsonjr@gmail.com>
To: pgsql-general@lists.postgresql.org
Subject: Re: Case Insensitive
Date: Thu, 28 Mar 2019 04:08:48 -0500
Message-ID: <c316dc7f-1eed-ea88-558a-76f00ada79e8@gmail.com> (raw)
In-Reply-To: <150586A3-A8F4-4B80-9A4B-310DE265B4B3@blighty.com>
References: <CAGuFTBU1fACZWYdVwU-HiBJWAt2QFRa9fkB+SovmVMoUjVbekw@mail.gmail.com>
	<CADp-Sm4RWjbFQix1_XH7hstj6FY-EZj-f2veSgR_Z7Ut=tdDEA@mail.gmail.com>
	<c86c6b09-31fa-f27d-b373-3d604d4ca2a0@gmail.com>
	<150586A3-A8F4-4B80-9A4B-310DE265B4B3@blighty.com>

On 3/28/19 3:33 AM, Steve Atkins wrote:
>
>> On Mar 28, 2019, at 8:29 AM, Ron <ronljohnsonjr@gmail.com> wrote:
>>
>> On 3/28/19 3:23 AM, Sameer Kumar wrote:
>> [snip]
>>> You can write a query with upper function:
>>>
>>> select * from emp where upper(ename)=upper('aaa');
>> That's a guaranteed table scan.
> Unless you have an index on upper(ename).

Are you sure?  I thought the lpart had to be immutable for the query 
optimizer to decide to use an index (and upper(ename) is mutable).

-- 
Angular momentum makes the world go 'round.

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