Handling tree structures — recursive SPs, nested sets, recursive CTEs

Managing recursive, tree-like data structures with Firebird Frank Ingermann

Welcome to this session ! … say Sparkies I and III

This session is... a piece of cake! about

Session overview ,[object Object],[object Object],[object Object],[object Object],[object Object]

What is a tree? ,[object Object],[object Object],[object Object]

Tree terms: Root, Nodes, Leafs ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Root node Node Leaf Leaf

Recursion types ,[object Object],[object Object],[object Object],[object Object],[object Object]

Tree „Cardinality“ ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Tree „Health“ (esp. in search trees) ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],8 nodes, 8 levels deep 31 nodes, 4 levels deep

Relations of nodes in trees ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Tree types ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Strategies for storing trees ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],NODE CHILD PARENT L R

Retrieving Trees from a DB ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Pros of Client-Side recursion ,[object Object],[object Object],[object Object],[object Object],[object Object]

Why we don‘t want client-side rec.: ,[object Object],[object Object],[object Object],[object Object],a) SLOW b) EXPENSIVE usually

Part 1 ,[object Object],[object Object],[object Object]

Stored Procedures ,[object Object],[object Object],[object Object]

Traversing trees with Selectable SPs ,[object Object],[object Object],[object Object],[object Object]

Recursive SPs: Pros and Cons ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Part 2 ,[object Object],Take some sets… … and another set… -> „S1“ -> „S2“ … then nest S1 into S2… … then, what do you get?

Nested Sets: Intro same data as Nested Sets : „ classical“ tree: Nested Sets are all about Containment ! … and NO, this slide is NOT about fried eggs!

Nested Sets: L and R values L R L R L R L R L R

Nested Sets: Rules for L and R ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Nested Sets: Pros and Cons

Part 3 ,[object Object],[object Object],[object Object]

Recursive CTEs: Pros and Cons ,[object Object],[object Object],[object Object],[object Object]

Recursive CTEs: Pros and Cons ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],just about everything else:

„ normal“ CTEs: Intro ,[object Object],[object Object],multiple CTEs are „chainable“ in one SELECT This is one SELECT you can send from a client „ ad hoc“

Recursive CTEs: Intro ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],!

Recursive CTEs: basic structure ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Traversing trees with recursive CTEs ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Server processing of rec. CTEs I ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],What you send: Server Phase I: Preparation WHERE CH.ID_Parent = :ID -- param

Server processing of rec. CTEs II ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],What you get back (Server Phase II: Execution) Recursion, one level down Loop (same level) Back up one level, „unwind“

Ordering Children in recursive CTEs ,[object Object],[object Object],[object Object]

Ordering Children in recursive CTEs ,[object Object],[object Object],[object Object],[object Object],( but : not yet implemented  )

Ordering Children in recursive CTEs ,[object Object],[object Object]

Ordering Children in recursive CTEs ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Ordering Children in recursive CTEs ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Part 4 ,[object Object],[object Object]

„ Fun“ with recursive CTEs ,[object Object],[object Object],Vanilla cake mixture Chocolate cake mixture Chocolate icing

Ingredients (RAW MATerials) ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Flower

Shugga baby! ,[object Object],[object Object],[object Object],[object Object],[object Object]

[object Object],[object Object],Questions ? Frank Ingermann [email_address] Want some cake ??? 

Handling tree structures — recursive SPs, nested sets, recursive CTEs

Empfohlen

Empfohlen

Weitere ähnliche Inhalte

Was ist angesagt?

Was ist angesagt? (8)

Ähnlich wie Handling tree structures — recursive SPs, nested sets, recursive CTEs

Ähnlich wie Handling tree structures — recursive SPs, nested sets, recursive CTEs (20)

Mehr von Mind The Firebird

Mehr von Mind The Firebird (20)

Kürzlich hochgeladen

Kürzlich hochgeladen (20)

Handling tree structures — recursive SPs, nested sets, recursive CTEs