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#11

Old

Thomas Winkler

Posts: n/a

Re: unique index considering nulls as equal - 06-12-2008 , 03:33 AM

Hi,

Quote:

test=*# create unique index idx_node on node(coalesce(pid,-1),t);

As you can see, you can insert distinct values for the text-field and
NULL in the pid, but no with NULL in the pid and the same text. Helps
that?

THX for your tip. It works great. I just didn't know the way of using
functions in indexes.

Thomas

Reply With Quote

#12

Old

Thomas Winkler

Posts: n/a

Re: unique index considering nulls as equal - 06-12-2008 , 03:33 AM

Hi,

Quote:

test=*# create unique index idx_node on node(coalesce(pid,-1),t);

As you can see, you can insert distinct values for the text-field and
NULL in the pid, but no with NULL in the pid and the same text. Helps
that?

THX for your tip. It works great. I just didn't know the way of using
functions in indexes.

Thomas

Reply With Quote

#13

Old

Thomas Winkler

Posts: n/a

Re: unique index considering nulls as equal - 06-12-2008 , 03:33 AM

Hi,

Quote:

test=*# create unique index idx_node on node(coalesce(pid,-1),t);

As you can see, you can insert distinct values for the text-field and
NULL in the pid, but no with NULL in the pid and the same text. Helps
that?

THX for your tip. It works great. I just didn't know the way of using
functions in indexes.

Thomas

Reply With Quote

#14

Old

Thomas Winkler

Posts: n/a

Re: unique index considering nulls as equal - 06-12-2008 , 03:33 AM

Hi,

Quote:

test=*# create unique index idx_node on node(coalesce(pid,-1),t);

As you can see, you can insert distinct values for the text-field and
NULL in the pid, but no with NULL in the pid and the same text. Helps
that?

THX for your tip. It works great. I just didn't know the way of using
functions in indexes.

Thomas

Reply With Quote

#15

Old

Thomas Winkler

Posts: n/a

Re: unique index considering nulls as equal - 06-12-2008 , 03:33 AM

Hi,

Quote:

test=*# create unique index idx_node on node(coalesce(pid,-1),t);

As you can see, you can insert distinct values for the text-field and
NULL in the pid, but no with NULL in the pid and the same text. Helps
that?

THX for your tip. It works great. I just didn't know the way of using
functions in indexes.

Thomas

Reply With Quote

#16

Old

Thomas Winkler

Posts: n/a

Re: unique index considering nulls as equal - 06-12-2008 , 03:33 AM

Hi,

Quote:

test=*# create unique index idx_node on node(coalesce(pid,-1),t);

As you can see, you can insert distinct values for the text-field and
NULL in the pid, but no with NULL in the pid and the same text. Helps
that?

THX for your tip. It works great. I just didn't know the way of using
functions in indexes.

Thomas

Reply With Quote

#17

Old

Thomas Winkler

Posts: n/a

Re: unique index considering nulls as equal - 06-12-2008 , 03:33 AM

Hi,

Quote:

test=*# create unique index idx_node on node(coalesce(pid,-1),t);

As you can see, you can insert distinct values for the text-field and
NULL in the pid, but no with NULL in the pid and the same text. Helps
that?

THX for your tip. It works great. I just didn't know the way of using
functions in indexes.

Thomas

Reply With Quote

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