[
https://issues.apache.org/jira/browse/OPTIQ-344?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Julian Hyde closed OPTIQ-344.
-----------------------------
> Lattice data structure
> ----------------------
>
> Key: OPTIQ-344
> URL: https://issues.apache.org/jira/browse/OPTIQ-344
> Project: Optiq
> Issue Type: New Feature
> Reporter: Julian Hyde
> Assignee: Julian Hyde
> Fix For: 0.9.1-incubating
>
>
> Add a "lattice" data structure, to organize, gather statistics on, and
> recommend materialized queries.
> DDL. Here is a possible SQL DDL syntax:
> CREATE LATTICE SalesStar AS
> SELECT *
> FROM SalesFact AS s
> JOIN TimeDim AS t USING (timeId)
> JOIN CustomerDim AS c USING (customerId)
> Structure. A materialized query would optionally belong to a lattice.
> Constraints. Creating a lattice implies that the first table is the fact
> table of a star schema, and all joins are many-to-one. That is, foreign keys,
> primary keys and NOT NULL constraints are implied.
> Statistics. When queries arrive that could use a lattice, a counter is
> incremented.
> Recommendation. An agent could recommend materialized queries to create based
> on static analysis of the star schema (e.g. table and column cardinalities),
> and perhaps statistics of past use.
> View matching. The optimizer uses a lattice to identify materialized queries
> that could satisfy a query. (Without a lattice, the such space would be much
> larger, because the optimizer would have to consider many join permutations.)
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
