SPIP
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validated by George.
{where}
Tuesday 23 August 2022 , by jack
In some cases, SPIP’s specific criteria do not allow a complex request to
be described. Loops can use the {where} criterion to directly specify the
WHERE of the SQL query.
The where criterion expects a single argument, which is the conditional
part of a (MY)SQL query. SPIP uses this value by combining it with the
other conditional elements from the other criteria in the loop.
**Examples **
The where criterion allows ORs to be performed:
<BOUCLE_or
(ARTICLES)
{statut=redac}
{where id_rubrique=10 OR id_rubrique=20}
>
It allows you to call MYSQL functions:
<BOUCLE_or
(ARTICLES)
{where YEAR(date_creation) > 1970}
>
It allows you to make subqueries (here in the plug-in info_site) :
{where id_organisation IN (SELECT id_objet FROM spip_projets_liens WHERE objet='organisation' AND id_projet=#ID_PROJET)}
The where criterion makes it possible to use a condition where the 2
terms of the test are fields of the table: we want to find the articles
with the same section id and sector id
<BOUCLE_where
(ARTICLES)
{where id_rubrique = id_secteur}
>
Note that it would have been possible to do it without where in all
these cases:
– with {id_rubrique IN #LIST{10,20}}
– with {date_creation>1970-01-01}
– with a joint in the SPIP loop
– with a wrapping loop
Preparing the condition
When there is a comma in the where expression, often because of a MYSQL
function call, include the condition in a #VAL tag.
Example :
{where #VAL{"DATE_ADD(date_debut,INTERVAL 2 WEEK)<date_fin"}}
When the conditions are even more complex, it is necessary to prepare the
query in a #SET :
#SET
{where, here complex calculation}
<BOUCLE_root_articles
(ARTICLES)
{...}
{where
#GET
{where}
}
>
Conditional where criterion
The criterion also allows comparison with the value of where passed into
the environment, if it exists: {where?}
— Sent by SPIP (https://www.spip.net/)
