Re: [Tcl-tdbc] SQL LIKE '%test%' problem

[Donal K. F. <don...@ma...>]

On 02/01/2013 18:03, to...@tu... wrote:
> On Wed, Jan 02, 2013 at 02:48:21PM +0000, Donal K. Fellows wrote:
>> you need to use something like this:
>>
>>    SELECT * FROM radcheck WHERE username LIKE '%' || :ffff || '%'
>>
>> (The “||” is the standard SQL string concatenation operator.)
>
> NOTE: the last MySQL I had contact with didn't know about ||.

Not my fault they ignore the SQL specification (probably due to the
widespread use of that operator for logical OR, but even so...).

> You'd have to use concat there, like so:
>
>>    SELECT * FROM radcheck WHERE username LIKE concat('%', :ffff ||, '%')
[...]

You have an extra “||” in there. Otherwise, that's correct.
http://en.wikibooks.org/wiki/SQL_Dialects_Reference/Functions_and_expressions/String_functions

> Unless tdbc::mysql is smart and understands the || operator: then you
> may ignore my talk above completely, that is.

It definitely doesn't; the core principle of TDBC is to not make the
client side over-smart, since that runs into real problems with more
complex cases.

Donal.