UNIQUE not unique with inheritance (workaround?)
Is there any workaround for this problem? I'm getting involved in a
project where inheritance is an incredibly useful feature, but the
non-unique issue could be a serious stumbling block. Is there any way
to work around it with a trigger or something?
On Sat, 2003-02-08 at 19:34, Samuel Sieb wrote:
Is there any workaround for this problem? I'm getting involved in a
project where inheritance is an incredibly useful feature, but the
non-unique issue could be a serious stumbling block. Is there any way
to work around it with a trigger or something?
Give each table in the hierarchy a foreign key reference to another
table which holds a unique list of the primary keys and a column that
says which table they are in. Use triggers to update this other table
and to prevent duplications in the hierarchy.
.
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Oliver Elphick Oliver.Elphick@lfix.co.uk
Isle of Wight, UK http://www.lfix.co.uk/oliver
GPG: 1024D/3E1D0C1C: CA12 09E0 E8D5 8870 5839 932A 614D 4C34 3E1D 0C1C
========================================
"But the LORD is in his holy temple; let all the earth
keep silence before him." Habakkuk 2:20
Or create a sequence, and make each table in the inheritance hierarchy
use the same sequence as it's default value.
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Oliver Elphick wrote:
On Sat, 2003-02-08 at 19:34, Samuel Sieb wrote:
Is there any workaround for this problem? I'm getting involved in a
project where inheritance is an incredibly useful feature, but the
non-unique issue could be a serious stumbling block. Is there any way
to work around it with a trigger or something?Give each table in the hierarchy a foreign key reference to another
table which holds a unique list of the primary keys and a column that
says which table they are in. Use triggers to update this other table
and to prevent duplications in the hierarchy..
--
Oliver Elphick Oliver.Elphick@lfix.co.uk
Isle of Wight, UK http://www.lfix.co.uk/oliver
GPG: 1024D/3E1D0C1C: CA12 09E0 E8D5 8870 5839 932A 614D 4C34 3E1D 0C1C
========================================
"But the LORD is in his holy temple; let all the earth
keep silence before him." Habakkuk 2:20---------------------------(end of broadcast)---------------------------
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