I have the following three tables: Venues, Events, Instance. Events have a Venue (Venues have many events), and Events have many Instances.
This is more of a generic SQL problem but I\'m using Firebird 2.5 if anyone knows of a Firebird/Interbase specific optimization.First, the following is a simplified example schema to illustrate the is
In MySQL 5.0.75-0ubuntu10.2 I\'ve got a fixed table layout like that: Table parent with an id Table parent2 with an id
I\'m designing a project for quizzes and quizz results. So I have two tables: quizz_result and quizz. quizz has primary key on ID and quizz_result has foreign key QUIZZ_ID to quizz identity.
What is the fastest/shortest/one-liner (not possible :p) way to build a unique tree of elements from a tree where many of the elements are duplicated/missing in some nodes, given the tree has a define
Is there any way I can prohibit MySQL from performing a full table scan when the result was not 开发者_开发问答found using indexes?
Relational databases are frequently used to store graphs in all their many flavors (trees, directed graphs, undirected graphs, ...).
I have three tables: USER: user_id (pk); username FIELD: field_id (pk); name METADATA: metadata_id 开发者_运维问答(pk); field_id (indx); user_id (indx); value
Query: select id, title from posts where id in (23,24,60,19,21,32,43,49,9,11,17,34,37,39,46,5 2,55) Explain plan:
I have a simple query which is returning records based on the field status not having certain values.
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