On 29.09.2017 11:03, Marko Tiikkaja wrote:
On Fri, Sep 29, 2017 at 9:31 AM, Konstantin Knizhnik
<k.knizh...@postgrespro.ru <mailto:k.knizh...@postgrespro.ru>> wrote:
I wonder why syntax error is produced in this case:
postgres=# create index metaindex on foo using
gin(to_tsvector('english', x)||to_tsvector('english',y));
ERROR: syntax error at or near "||"
LINE 1: ...taindex on foo using gin(to_tsvector('english',
x)||to_tsvec...
^
[ .. ]
/|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.
So documentations states that sometimes it is possible to avoid
parentheses, but it is unclear why I have to use double
parentheses...
I think that either grammar should be fixed, either documentation
should be updated.
Your expression is clearly not a function call, it's a concatenation
of two of them. The documentation seems perfectly accurate to me?
O, sorry!
You are right. I just didn't notice extra parenthesis in CREATE INDEX
syntax in case of using expressions.
--
Konstantin Knizhnik
Postgres Professional: http://www.postgrespro.com
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