ERP5 uses ZSQLCatalog, which is like Zope's ZCatalog, but using a relational database as a backend. ZSQLCatalog allows to query a Zope Catalog with a combination of traditional Zope Catalog queries (field based, text based) and with complex queries which are implicitly implemented as SQL methods. ComplexQuery defines a faster,more efficient and more complex search for information by using nested queries.It allows you to do a search using a more specific and precise set of criteria. In fact,ComplexQuery represents a Query with subqueries, combined with an operator. Typically, the operator can be anything, but it is generally "AND" or "OR".
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Example¶
from Products.ZSQLCatalog.SQLCatalog import ComplexQuery
from Products.ZSQLCatalog.SQLCatalog import Query
query=ComplexQuery(Query(title='%rose%'),
Query(portal_type='Person'),
logical_operator="AND")
return context.portal_catalog(query=query)
This will retrieve all documents of portal type 'Person' with a title containing 'rose'.
Combining Complex Queries¶
Lets first consider that with the method z_create_birth_details, we have already defined a table birth_details with custom fields birth_date and birthplace_text.
create table `birth_details` (
`uid` BIGINT(20) UNSIGNED NOT NULL,
`birth_date` datetime,
`birthplace_text` varchar(255) default '',
PRIMARY KEY (`uid`),
KEY `birth_date` (`birth_date`),
KEY `birthplace_text` (`birthplace_text`)
) TYPE=InnoDB;
For more information, on how to add a table to the catalog, please refer to HowToAddTableToCatalog. We can then use the following example to find all the persons that were born within a certain range of date.
from Products.ZSQLCatalog.SQLCatalog import ComplexQuery
from Products.ZSQLCatalog.SQLCatalog import Query
return context.portal_catalog(query=Query(
birth_date=[DateTime(1980, 1, 1), DateTime(1980, 12, 31)],
range='minmax'))
This will return all persons who were born between January 1st,1980 and December 31st,1980.
The following examples show the use of multiple subcomplexqueries to create a higher and more complex ComplexQuery.
from Products.ZSQLCatalog.SQLCatalog import ComplexQuery
from Products.ZSQLCatalog.SQLCatalog import Query
query = ComplexQuery(ComplexQuery(Query(title='%jean%'),
Query(birth_date='1985/02/20'),
Query(portal_type='Person'),
logical_operator="AND"),
ComplexQuery(Query(title='%jean%'),
Query(birthplace_text='Paris'),
Query(portal_type='Person'),
logical_operator="AND"),
ComplexQuery(Query(birth_date='1985/02/20'),
Query(birthplace_text='Paris'),
Query(portal_type='Person'),
logical_operator="AND"),
logical_operator="OR")
return context.portal_catalog(query=query)
This will use the catalog to return all persons with a title containing 'jean' and who were born on '1985/02/20' or all persons with a title containing 'jean' and who were born in 'Paris' or all persons who were born on 1985/02/20 in Paris.
Sorting Complex Queries¶
The results of the queries can also be sorted by using select_expression and selection_expression_key to define what the sorting will be based on.
from Products.ZSQLCatalog.SQLCatalog import ComplexQuery
from Products.ZSQLCatalog.SQLCatalog import Query
person_title='jean pierre boulanger'
query = ComplexQuery(ComplexQuery(Query(title=person_title),
Query(birth_date='1985/02/20'),
Query(portal_type='Person'),
logical_operator="AND"),
ComplexQuery(Query(title=person_title),
Query(birthplace_text='Paris'),
Query(portal_type='Person'),
logical_operator="AND"),
ComplexQuery(Query(birth_date='1985/02/20'),
Query(birthplace_text='Paris'),
Query(portal_type='Person'),
logical_operator="AND"),
logical_operator="OR")
select_expression = \
"""((title ="%s"))AS result_order """ % (person_title)
return context.portal_catalog(query=query,
select_expression=select_expression,
sort_on=(('result_order', 'DESC', 'int'),),
select_expression_key='result_order')
This will use the catalog to return all persons with a title containing person_title and who were born on '1985/02/20' or all persons with a title containing person_tile and who were born in 'Paris' or all persons who were born on 1985/02/20 in Paris, but it will sort them so that the persons with a title containing person_title will always come first.
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