Lucene Group

Represents a group of search conditions combined using boolean logic for Azure AI Search queries.

Remarks

The Lucene Group class is used to combine multiple Lucene Query conditions into a single logical group, allowing you to construct complex search expressions using boolean operators such as AND and OR. Group queries enable advanced filtering and retrieval scenarios by specifying how multiple conditions should be evaluated together.

Purpose and Usage

• Use Lucene Group to combine two or more search conditions, such as words, phrases, or other groups.
• Supports boolean logic, enabling you to require that all conditions are met (AND) or that any condition is met (OR).
• Can be nested to create highly flexible and expressive search queries.

Lucene Syntax Examples: Grouping and Order of Operations

Groups are indicated by parentheses in Lucene syntax. Parentheses control the order of operations and precedence when combining multiple conditions and operators.

Basic Grouping:
(invoice AND paid)
Returns documents containing both "invoice" and "paid".

OR Grouping:
(contract OR agreement)
Returns documents containing either "contract" or "agreement".

Nested Groups:
((invoice AND paid) OR (contract AND signed))
Returns documents that either contain both "invoice" and "paid", or both "contract" and "signed".

Operator Precedence Example:
invoice AND (paid OR overdue)
Returns documents containing "invoice" and either "paid" or "overdue".

Complex Example:
(category:finance AND (invoice OR receipt)) OR (category:legal AND contract)
Returns documents in the "finance" category that contain either "invoice" or "receipt", or documents in the "legal" category that contain "contract".

Grouping with parentheses ensures that your intended logic is preserved, especially when mixing AND/OR operators. Without grouping, operator precedence may lead to unexpected results.

Configuration Guidance

• Add one or more Lucene Query objects to the 'Conditions' property to define the set of criteria to be evaluated.
• Set the 'Operator' property to control whether all conditions must be met (AND) or any condition may be met (OR). If not set, the default behavior is OR.
• Combine with the 'Field Name' and 'Not' properties (inherited from Lucene Query) to further refine your search.

Best Practices

• Use groups to organize and clarify complex search logic, especially when combining multiple terms or phrases.
• Choose the appropriate boolean operator to match your retrieval goals (e.g., AND for strict filtering, OR for broader results).
• Nest groups as needed to represent complex logic, but keep queries as simple as possible for maintainability.
• Test group queries in the Azure portal or Grooper UI to ensure they return the expected results.

Example Scenarios

• Find documents containing both invoice and paid:
  (invoice AND paid)
• Find documents containing either contract or agreement:
  (contract OR agreement)
• Combine groups for advanced logic:
  ((invoice AND paid) OR (contract AND signed))

Properties

Name	Type		Description
Operator	BooleanOperator?	►	Specifies whether all or any of the conditions in the group must be met (AND/OR). Can be one of the following types: Value Description AND OR The 'Operator' property determines how the conditions in the group are combined: Set to AND to require that all conditions are satisfied for a document to match. Set to OR to allow a document to match if any condition is satisfied. If not set, the default behavior is OR. Use this property to control the strictness of your group query. For more information about boolean operators, see the Azure AI Search documentation on Lucene syntax. Example: To require both invoice and paid: set Operator to AND. To allow either contract or agreement: set Operator to OR.
Conditions	Lucene Query[]	►	The list of Lucene Query conditions to be evaluated in the group. The 'Conditions' property defines the set of search expressions that make up the group. Each condition can be a word, phrase, or another group, allowing for flexible and nested logic. Add one or more Lucene Query objects to specify the criteria to be combined. The group will evaluate these conditions using the selected 'Operator' (AND/OR). Use groups to organize related conditions and clarify complex search requirements. Example: To search for documents containing both invoice and paid, add two Lucene Word queries to Conditions and set Operator to AND. To search for documents containing either contract or agreement, add two Lucene Word queries to Conditions and set Operator to OR.
Field Name	String	►	The name of a field to restrict the search. The 'Field Name' property specifies the field in the Azure AI Search index to which the search expression applies. Fielded search operations use the fieldName:searchExpression syntax, allowing you to target specific fields for more precise results. Set this property to the name of a searchable field in your index. If left blank, the search applies to all searchable fields. Example: genre: jazz NOT history artists:("Miles Davis" "John Coltrane") Use quotation marks for multi-word phrases and ensure the field exists in your index schema.
Not	Boolean	►	When set to true, the query will exclude matching documents. DefaultFalse The 'Not' property enables exclusion logic in the search query, allowing you to filter out documents that match the specified criteria. Set to true to prepend NOT to the search expression. Useful for refining results by excluding unwanted terms or phrases. Example: "Oklahoma City" NOT Edmond This query finds documents containing "Oklahoma City" but not the term "Edmond". Note: Queries with a single negation (e.g., NOT "Oklahoma City") are not allowed in Azure AI Search.