Struct SelectModifiers 

pub struct SelectModifiers {
    pub high_priority: bool,
    pub straight_join: bool,
    pub sql_small_result: bool,
    pub sql_big_result: bool,
    pub sql_buffer_result: bool,
    pub sql_no_cache: bool,
    pub sql_calc_found_rows: bool,
}

MySQL-specific SELECT modifiers that appear after the SELECT keyword.

These modifiers affect query execution and optimization. They can appear in any order after SELECT and before the column list, can be repeated, and can be interleaved with DISTINCT/DISTINCTROW/ALL:

SELECT
    [ALL | DISTINCT | DISTINCTROW]
    [HIGH_PRIORITY]
    [STRAIGHT_JOIN]
    [SQL_SMALL_RESULT] [SQL_BIG_RESULT] [SQL_BUFFER_RESULT]
    [SQL_NO_CACHE] [SQL_CALC_FOUND_ROWS]
    select_expr [, select_expr] ...

See MySQL SELECT.

Fields

high_priority: bool

HIGH_PRIORITY gives the SELECT higher priority than statements that update a table.

https://dev.mysql.com/doc/refman/8.4/en/select.html

straight_join: bool

STRAIGHT_JOIN forces the optimizer to join tables in the order listed in the FROM clause.

https://dev.mysql.com/doc/refman/8.4/en/select.html

sql_small_result: bool

SQL_SMALL_RESULT hints that the result set is small, using in-memory temp tables.

https://dev.mysql.com/doc/refman/8.4/en/select.html

sql_big_result: bool

SQL_BIG_RESULT hints that the result set is large, using disk-based temp tables.

https://dev.mysql.com/doc/refman/8.4/en/select.html

sql_buffer_result: bool

SQL_BUFFER_RESULT forces the result to be put into a temporary table to release locks early.

https://dev.mysql.com/doc/refman/8.4/en/select.html

sql_no_cache: bool

SQL_NO_CACHE tells MySQL not to cache the query result. (Deprecated in 8.4+.)

https://dev.mysql.com/doc/refman/8.4/en/select.html

sql_calc_found_rows: bool

SQL_CALC_FOUND_ROWS tells MySQL to calculate the total number of rows. (Deprecated in 8.0.17+.)

• MySQL SELECT modifiers
• FOUND_ROWS()

Implementations

impl SelectModifiers

pub fn is_any_set(&self) -> bool

Returns true if any of the modifiers are set.

Trait Implementations

impl Clone for SelectModifiers

fn clone(&self) -> SelectModifiers

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SelectModifiers

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

Formats the value using the given formatter.

impl Default for SelectModifiers

fn default() -> SelectModifiers

Returns the “default value” for a type.

impl Display for SelectModifiers

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

Formats the value using the given formatter.

impl Eq for SelectModifiers

impl Hash for SelectModifiers

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for SelectModifiers

fn cmp(&self, other: &SelectModifiers) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for SelectModifiers

fn eq(&self, other: &SelectModifiers) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for SelectModifiers

fn partial_cmp(&self, other: &SelectModifiers) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for SelectModifiers

impl Visit for SelectModifiers

fn visit<V>(&self, visitor: &mut V) -> ControlFlow<<V as Visitor>::Break>

where V: Visitor,

Visit this node with the provided Visitor.

impl VisitMut for SelectModifiers

fn visit<V>(&mut self, visitor: &mut V) -> ControlFlow<<V as VisitorMut>::Break>

where V: VisitorMut,

Mutably visit this node with the provided VisitorMut.