The SYSFOREIGNKEY view is provided for compatibility with older versions of SQL Anywhere that offered a SYSFOREIGNKEY system table. However, the previous SYSFOREIGNKEY system table has been replaced by the ISYSFKEY system table, and its corresponding SYSFKEY system view, which you should use instead.
A foreign key is a relationship between two tables—the foreign table and the primary table. Every foreign key is defined by one row in SYSFOREIGNKEY and one or more rows in SYSFKCOL. SYSFOREIGNKEY contains general information about the foreign key while SYSFKCOL identifies the columns in the foreign key and associates each column in the foreign key with a column in the primary key of the primary table.
The tables and columns that make up this view are provided in the SQL statement below. To learn more about a particular table or column, use the links provided beneath the view definition.
ALTER VIEW "SYS"."SYSFOREIGNKEY" as select b.foreign_table_id, b.foreign_index_id as foreign_key_id, a.object_id, b.primary_table_id, p.root, b.check_on_commit, b.nulls, a.index_name as role, r.remarks, b.primary_index_id, a.not_enforced as fk_not_enforced, 10 as hash_limit from(SYS.ISYSIDX as a left outer join SYS.ISYSPHYSIDX as p on(a.table_id = p.table_id and a.phys_index_id = p.phys_index_id)) left outer join SYS.ISYSREMARK as r on(a.object_id = r.object_id) ,SYS.ISYSFKEY as b where a.table_id = b.foreign_table_id and a.index_id = b.foreign_index_id
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