Fujitsu UDS/SQL V2.5 Manuel D’Utilisation
Types of access
Schema DDL
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U929-J-Z125-9-76
Generating an additional access path via secondary key
SEARCH KEY IS item-name,... USING INDEX [NAME IS name]
DUPLICATES ARE[ NOT] ALLOWED
DUPLICATES ARE[ NOT] ALLOWED
A key defined by means of SEARCH-KEY IS... is called a SEARCH key or secondary key.
It may consist of more than one item.
It may consist of more than one item.
item-name
specifies the item(s) comprising the key. All items have to be part of the member.
name
specifies the name of the table. This name is referred to in SSL statements concerning
the table.
DUPLICATES ARE[ NOT] ALLOWED specifies whether UDS/SQL is to accept or reject
duplicate key values.
duplicate key values.
Based on this definition, UDS/SQL sets up a SEARCH key table on set level or a set
SEARCH key table for each set occurrence of the set. This table represents a unique
reference between secondary key value, database key value and physical address for each
record belonging to the set occurrence. It must be a multi-level table. When the position of
the record is changed, the physical address is not automatically updated.
SEARCH key table for each set occurrence of the set. This table represents a unique
reference between secondary key value, database key value and physical address for each
record belonging to the set occurrence. It must be a multi-level table. When the position of
the record is changed, the physical address is not automatically updated.
Several independent secondary keys can be defined for each set.