Struct QueryCondition 

pub struct QueryCondition { /* private fields */ }

QueryCondition — Spec §2.2.2.5.9. Extends ReadCondition with a SQL filter expression (DDS-DCPS Annex B). The filter is evaluated per sample (see Self::evaluate); the parse step happens once in the constructor.

Implementations

impl QueryCondition

pub fn new( base: Arc<ReadCondition>, query_expression: impl Into<String>, query_parameters: Vec<String>, ) -> Result<Arc<Self>>

Constructor — Spec §2.2.2.5.2.5 create_querycondition / §2.2.2.5.9. The SQL expression is parsed immediately; a syntactically invalid expression returns BadParameter.

Errors

BadParameter if the SQL expression does not parse.

pub fn evaluate<R: RowAccess>(&self, row: &R) -> Result<bool>

Evaluates the SQL filter against a sample. Spec §2.2.2.5.9.6 — only samples with evaluate(...)==Ok(true) count toward the read_w_condition/take_w_condition result.

Parameter strings are converted into String Values; the caller can pass typed parameters via Self::evaluate_with_values.

Errors

Lock poisoning or SQL eval error (UnknownField/TypeMismatch/ MissingParam).

pub fn evaluate_with_values<R: RowAccess>( &self, row: &R, params: &[Value], ) -> Result<bool>

Like Self::evaluate, but with an explicitly typed parameter slice (e.g. for int/float parameters that would not match as a string cast).

Errors

SQL eval error.

pub fn get_query_expression(&self) -> &str

Spec §2.2.2.5.9.4 get_query_expression.

pub fn get_query_parameters(&self) -> Vec<String>

Spec §2.2.2.5.9.5 get_query_parameters.

pub fn set_query_parameters(&self, params: Vec<String>) -> Result<()>

Spec §2.2.2.5.9.6 set_query_parameters.

Errors

PreconditionNotMet on lock poisoning.

pub fn base(&self) -> &Arc<ReadCondition>

Access to the base ReadCondition (Spec: QueryCondition extends ReadCondition).

Trait Implementations

impl Condition for QueryCondition

fn get_trigger_value(&self) -> bool

True if the event of this condition is currently pending. Spec §2.2.2.1.6 get_trigger_value.

impl Debug for QueryCondition

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.