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Inner Join - Explicit vs Implicit Join Performance
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* Inner Join - Explicit vs Implicit Join Performance
@ 2011-10-19 10:39  Gnanakumar <gnanam@zoniac.com>
  0 siblings, 1 reply; 2+ messages in thread

From: Gnanakumar @ 2011-10-19 10:39 UTC (permalink / raw)
  To: pgsql-performance

Hi,

In PostgreSQL, is there any performance difference between queries written
using "explicit join notation" vs "implicit join notation" in complex
queries?

EXAMPLE: Simple "explicit join notation"
SELECT *
FROM   employee INNER JOIN department
ON     employee.DepartmentID = department.DepartmentID;

EXAMPLE: Simple "implicit join notation"
SELECT *
FROM   employee, department 
WHERE  employee.DepartmentID = department.DepartmentID;

Regards,
Gnanam





^ permalink  raw  reply  [nested|flat] 2+ messages in thread

* Re: Inner Join - Explicit vs Implicit Join Performance
@ 2011-10-19 11:14  Pavel Stehule <pavel.stehule@gmail.com>
  parent: Gnanakumar <gnanam@zoniac.com>
  0 siblings, 0 replies; 2+ messages in thread

From: Pavel Stehule @ 2011-10-19 11:14 UTC (permalink / raw)
  To: gnanam@zoniac.com; +Cc: pgsql-performance

Hello

no, there is no difference - you can check it via EXPLAIN statement

Regards

Pavel Stehule

2011/10/19 Gnanakumar <gnanam@zoniac.com>:
> Hi,
>
> In PostgreSQL, is there any performance difference between queries written
> using "explicit join notation" vs "implicit join notation" in complex
> queries?
>
> EXAMPLE: Simple "explicit join notation"
> SELECT *
> FROM   employee INNER JOIN department
> ON     employee.DepartmentID = department.DepartmentID;
>
> EXAMPLE: Simple "implicit join notation"
> SELECT *
> FROM   employee, department
> WHERE  employee.DepartmentID = department.DepartmentID;
>
> Regards,
> Gnanam
>
>
>
> --
> Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-performance
>



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