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left | right | inner JOIN LATERAL

SQL-Server:

CROSS | OUTER APPLY

INNER JOIN LATERAL is the same as CROSS APPLY
and LEFT JOIN LATERAL is the same as OUTER APPLY

Example usage (PostgreSQL 9.3+):

SELECT * FROM T_Contacts

--LEFT JOIN T_MAP_Contacts_Ref_OrganisationalUnit ON MAP_CTCOU_CT_UID = T_Contacts.CT_UID AND
MAP_CTCOU_SoftDeleteStatus = 1
--WHERE T_MAP_Contacts_Ref_OrganisationalUnit.MAP_CTCOU_UID IS NULL -- 989

LEFT JOIN LATERAL
(
SELECT
--MAP_CTCOU_UID
MAP_CTCOU_CT_UID
,MAP_CTCOU_COU_UID
,MAP_CTCOU_DateFrom
,MAP_CTCOU_DateTo
FROM T_MAP_Contacts_Ref_OrganisationalUnit
WHERE MAP_CTCOU_SoftDeleteStatus = 1
AND MAP_CTCOU_CT_UID = T_Contacts.CT_UID

/*
AND
(
(__in_DateFrom <= T_MAP_Contacts_Ref_OrganisationalUnit.MAP_KTKOE_DateTo)
AND
(__in_DateTo >= T_MAP_Contacts_Ref_OrganisationalUnit.MAP_KTKOE_DateFrom)
)
*/
ORDER BY MAP_CTCOU_DateFrom
LIMIT 1
) AS FirstOE

And for SQL-Server

SELECT * FROM T_Contacts

--LEFT JOIN T_MAP_Contacts_Ref_OrganisationalUnit ON MAP_CTCOU_CT_UID = T_Contacts.CT_UID AND
MAP_CTCOU_SoftDeleteStatus = 1
--WHERE T_MAP_Contacts_Ref_OrganisationalUnit.MAP_CTCOU_UID IS NULL -- 989

-- CROSS APPLY -- = INNER JOIN
OUTER APPLY -- = LEFT JOIN
(
SELECT TOP 1
--MAP_CTCOU_UID
MAP_CTCOU_CT_UID
,MAP_CTCOU_COU_UID
,MAP_CTCOU_DateFrom

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