Struct QueryBuilder 

pub struct QueryBuilder { /* private fields */ }

Builds SQL queries from FHIR search parameters.

Implementations

impl QueryBuilder

pub fn new( tenant_id: impl Into<String>, resource_type: impl Into<String>, ) -> Self

Creates a new query builder.

pub fn with_param_offset(self, offset: usize) -> Self

Sets the parameter offset for embedded subqueries.

When the generated SQL will be embedded in an outer query that already uses params ?1, ?2, etc., set this offset so the subquery’s search params don’t conflict.

The offset should be the total number of params used by the outer query BEFORE the subquery. For example:

• Outer query uses ?1 (tenant) and ?2 (type): offset = 2
• Outer query uses ?1-?4 for cursor pagination: offset = 4

Note: The subquery still references ?1 and ?2 for tenant/resource type since those bind to the same values as the outer query.

pub fn build(&self, query: &SearchQuery) -> SqlFragment

Builds a complete search query.

Returns SQL that selects matching resource IDs from the search_index table.

pub fn build_order_by(&self, query: &SearchQuery) -> String

Builds an ORDER BY clause.

Supports multiple sort directives (e.g., _sort=name,-birthdate). Each directive is processed in order, with a tie-breaker (id ASC) added at the end for stable pagination.

Supported Sort Parameters

• _id: Sorts by resource logical ID
• _lastUpdated: Sorts by last modification timestamp

Other sort parameters are currently mapped to resource ID as a fallback. Full support for arbitrary search parameters would require additional SQL joins with the search_index table.

pub fn build_limit(&self, query: &SearchQuery) -> String

Builds a LIMIT clause.

pub fn get_used_params(query: &SearchQuery) -> HashSet<String>

Returns the set of parameter names used in a query.