Re: BUG #8211: Syntax error when creating index on expression - Mailing list pgsql-bugs

On Wed, Jun 5, 2013 at 8:24 AM, <acizov@gmail.com> wrote:
>
> Bug reference:      8211
> Logged by:          Andrey Cizov
> Email address:      acizov@gmail.com
> PostgreSQL version: 9.2.3
> Operating system:   Windows
> Description:
>
> CREATE INDEX heuristic ON foos (1 / (a + b))
>
> causes:
>
> ERROR:  syntax error at or near "1"
> LINE 1: CREATE INDEX heuristic ON foos (1 / (a + b))
>                                         ^
>
> ********** Error **********
>
> ERROR: syntax error at or near "1"
> SQL state: 42601
> Character: 33
>
> While:
>
> CREATE INDEX heuristic ON foos ((1 / (a + b)))
>
> Execution successful



Did you look at the docs?

http://www.postgresql.org/docs/current/static/sql-createindex.html

expression

An expression based on one or more columns of the table. The expression
usually must be written with surrounding parentheses, as shown in the
syntax. However, the parentheses can be omitted if the expression has the
form of a function call.