Struct Field

pub struct Field { /* private fields */ }

Struct to facilitate the definiion of a condition associated with a given field For example, create a condition to filter name column equal to ‘Jane’:

let conn = rusqlite::Connection::open_in_memory().unwrap();
use derive_sql::structs::{Field, filter, order};
use derive_sql::traits::{FlavoredFilter, FlavoredOrder};

let condition: filter::Condition<_> = Field::from("name").eq("Jane");
assert!(condition.filter(&conn).unwrap().eq("`name` = 'Jane'"));

let condition: order::Condition = Field::from("name").ascending();
assert!(condition.as_order_clause(&conn).unwrap().eq("`name` ASC"));

let condition: filter::Condition<_> = Field::from_table_column("table", "col").eq("val");
assert!(condition.filter(&conn).unwrap().eq("`table`.`col` = 'val'"));

Implementations

impl Field

pub fn from(label: &str) -> Field

Create a new field with the given label

pub fn from_table_column(table: &str, label: &str) -> Field

Create a new field with the given label

pub fn is_none(self) -> Condition<bool>

Generate a test on Null

pub fn is_some(self) -> Condition<bool>

Generate a test on Not Null

pub fn eq<T>(self, t: T) -> Condition<T>

where Value<T>: From<T>, T: Display,

Generate an ‘equal’ condition

pub fn ne<T>(self, t: T) -> Condition<T>

where Value<T>: From<T>, T: Display,

Generate a ‘not-equal’ condition

pub fn gt<T>(self, t: T) -> Condition<T>

where Value<T>: From<T>, T: Display,

Generate a ‘greater than’ condition

pub fn ge<T>(self, t: T) -> Condition<T>

where Value<T>: From<T>, T: Display,

Generate a ‘greater equal’ condition

pub fn lt<T>(self, t: T) -> Condition<T>

where Value<T>: From<T>, T: Display,

Generate a ‘lower than’ condition

pub fn le<T>(self, t: T) -> Condition<T>

where Value<T>: From<T>, T: Display,

Generate a ‘lower equal’ condition

pub fn ascending(self) -> Condition

Generate an ascending order clause condition

pub fn descending(self) -> Condition

Generate a descending order clause condition