Struct DataQuery 

pub struct DataQuery { /* private fields */ }

A lazy query builder.

Build the query using the fluent API, then call execute to materialise the results.

Implementations

impl DataQuery

pub fn from(source: DataSource) -> Self

Create a query from a DataSource.

pub fn select(self, columns: &[&str]) -> Self

Restrict the projected columns. Pass an empty slice to select all.

pub fn filter( self, predicate: impl Fn(&Row) -> bool + Send + Sync + 'static, ) -> Self

Add a row-level filter predicate. Multiple calls are ANDed together.

pub fn limit(self, n: usize) -> Self

Limit the number of result rows.

pub fn order_by(self, column: &str, ascending: bool) -> Self

Sort the result by a column. ascending = true → smallest first.

pub fn execute(self) -> Result<QueryResult>

Execute the query and return the materialised result.