Re: @ operator - Mailing list pgsql-general

From David G. Johnston
Subject Re: @ operator
Date
Msg-id CAKFQuwYdzd+=wde52AMnN1_rQrCEQP4d-zbKQnDfq-t96Kx90Q@mail.gmail.com
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In response to Re: @ operator  ("David G. Johnston" <david.g.johnston@gmail.com>)
Responses Re: @ operator
List pgsql-general
On Thursday, September 17, 2015, David G. Johnston <david.g.johnston@gmail.com> wrote:
On Thursday, September 17, 2015, Антон Бушмелев <bushmelev.aa@gmail.com> wrote:
Hello, google nothing  for @ operator =(,  what does this mean  field1 <@ ( subquery ) ?


It would depend on what field1 is.

Typically <@ is a contains/contained-by operator.  Is this context the subquery is checked to see if it contains the value of field1.

David J. 

To clarify I think that it means that for each row returned by the subquery, the value of filed1 is checked to see if the field in the subquery contains the given value.  Use use ANY/ALL to indicate whether to care if on,y so,e rows or all rows need match in order for the entire expression to pass.

David J.

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