1. Authors: Magesh Jayapandian and H.V. Jagadish Chris Truszkowski

2. Introduction Forms, forms, forms Form Generation Class and Analysis Query Generation Evaluation

3. Introduction class, database form: Database form, class. Introductions made Database:Query Form relationship Good form time consuming Query->Form translation not obvious Query/schema complexity ^ -> Form generation harder Tools exist, but do not shoulder entire burden

4. Forms: (N) a definition A visual representation of a query operation. Meaningful layout crucial to understanding Form elements: Constraint Result Aggregate Ordering Disjunction Join

6. Generation after generation… Query Analysis Selection Projection Sort Aggregate Join Disjunction Structure Query vs. Schema grouping

7. Class analysis time Similarity analysis Shared elements Jaccard distance Clustering Classes of similar queries Complexity

8. Query generation Reverse reverse … Simple Queries No Join Single Group Complex Queries Binding variable Algorithm GenerateQuery Input: A filled form F Output: An XQuery expression X foreach join-element j ∈ T, the relationship tree of F do Create a new binding variable v1 for the entity referenced by the left-hand side of the join condition (if it does not already exist); Create a binding variable v2 for the entity referenced by the right-hand side of the join condition (if it does not already exist); Assign v1, v2 to the group containing j; if j denotes a nested relationship then Construct a new query block b and record the current query block as its parent; Add b to B, the set of query blocks; if no join-element found then Create a single binding variable v and assign it to the root group; foreach form-group g ∈ T do Partition the form-elements in g between the two binding variables by schematic similarity; foreach binding variable v do Assign v to the lowest common ancestor of schema entities (referenced by elements) that are assigned to it; foreach query block b ∈ B do Assign a unique variable name to b and denote its associated schematic entity as its scope; Create a for clause using the variable name and scope; Create a predicate for each constraint-specification or join-specification element and add it to the where clause; Create a projection for each result-display element and add it to the return clause; Create an orderby attribute for each result-ordering element and add it to the orderby clause; foreach query block b ∈ B do Construct a let-clause that connects b to its parent block; Construct the XQuery expression X recursively using a DFS traversal of the query blocks;

9. Evaluation Size of form set Complexity of forms Expresivity Complexity vs Expresivity

10. Questions? Preguntas? Fragen?