Struct SqliteFunctionBehavior 

pub struct SqliteFunctionBehavior(/* private fields */);

Available on crate feature __sqlite-shared only.

Flags controlling SQLite custom function behavior.

These flags are passed to sqlite3_create_function_v2() and control how SQLite treats the function in various contexts.

Availability

• DETERMINISTIC: SQLite 3.8.3 (2014-02)
• DIRECTONLY, INNOCUOUS: SQLite 3.31.0 (2020-01)
• SUBTYPE: SQLite 3.30.0 (2019-10)

Security Considerations

When using SqliteConnection::set_trusted_schema(false) for security hardening, custom functions must be marked with INNOCUOUS to be callable from views, triggers, CHECK constraints, DEFAULT expressions, generated columns, and expression indexes.

Conversely, functions with side effects or that expose sensitive state should be marked with DIRECTONLY to prevent them from being called via malicious schema objects in untrusted database files.

Example

use diesel::sqlite::SqliteFunctionBehavior;

// Deterministic function (most common case)
let flags = SqliteFunctionBehavior::DETERMINISTIC;
assert!(flags.contains(SqliteFunctionBehavior::DETERMINISTIC));

// Non-deterministic function (e.g., random())
let flags = SqliteFunctionBehavior::empty();
assert!(flags.is_empty());

// Safe for use in untrusted schemas (views, triggers, etc.)
let flags = SqliteFunctionBehavior::DETERMINISTIC | SqliteFunctionBehavior::INNOCUOUS;
assert!(flags.contains(SqliteFunctionBehavior::DETERMINISTIC));
assert!(flags.contains(SqliteFunctionBehavior::INNOCUOUS));

// Has side effects, block from schema objects
let flags = SqliteFunctionBehavior::DIRECTONLY;
assert!(flags.contains(SqliteFunctionBehavior::DIRECTONLY));

When registering a custom SQL function:

use diesel::sqlite::SqliteFunctionBehavior;
use diesel::prelude::*;

// Use SqliteFunctionBehavior when registering SQL functions
conn.register_sql_function::<diesel::sql_types::Text, diesel::sql_types::Text, _, _, _>(
    "my_upper",
    SqliteFunctionBehavior::DETERMINISTIC | SqliteFunctionBehavior::INNOCUOUS,
    |x: String| x.to_uppercase(),
)?;

Implementations

impl SqliteFunctionBehavior

pub const DETERMINISTIC: Self

The function always returns the same result given the same inputs within a single SQL statement.

This allows SQLite to optimize by caching results and factoring the function out of inner loops. Most pure functions should use this flag.

Availability

Requires SQLite 3.8.3 (2014-02) or later.

Example

abs(x) is deterministic. random() is not.

pub const DIRECTONLY: Self

The function cannot be called from schema objects (views, triggers, CHECK constraints, DEFAULT expressions, generated columns, or expression indexes).

Use this for functions that:

• Have side effects (network, file I/O, logging, etc.)
• Return sensitive application state
• Should not be triggered by opening an untrusted database

Availability

Requires SQLite 3.31.0 (2020-01) or later.

Security Recommendation

Mark all functions with side effects or that expose internal state with DIRECTONLY to prevent schema injection attacks.

pub const INNOCUOUS: Self

The function is safe to call from untrusted schema contexts.

When SqliteConnection::set_trusted_schema(false) is set, only functions marked INNOCUOUS can be called from schema objects (views, triggers, CHECK constraints, DEFAULT expressions, generated columns, expression indexes).

Availability

Requires SQLite 3.31.0 (2020-01) or later.

Safety Requirements

Only mark a function as INNOCUOUS if it:

• Has no side effects
• Does not reveal internal application state
• Output depends solely on its input parameters

Security Warning

Incorrectly marking a function as INNOCUOUS can create security vulnerabilities when processing untrusted database files. An attacker could craft a database with malicious views or triggers that invoke your function in unexpected ways.

pub const SUBTYPE: Self

The function may call sqlite3_value_subtype() to inspect the subtype of its arguments.

Availability

Requires SQLite 3.30.0 (2019-10) or later.

impl SqliteFunctionBehavior

pub const fn empty() -> Self

Get a flags value with all bits unset.

pub const fn all() -> Self

Get a flags value with all known bits set.

pub const fn bits(&self) -> i32

Get the underlying bits value.

The returned value is exactly the bits set in this flags value.

pub const fn from_bits(bits: i32) -> Option<Self>

Convert from a bits value.

This method will return None if any unknown bits are set.

pub const fn from_bits_truncate(bits: i32) -> Self

Convert from a bits value, unsetting any unknown bits.

pub const fn from_bits_retain(bits: i32) -> Self

Convert from a bits value exactly.

pub fn from_name(name: &str) -> Option<Self>

Get a flags value with the bits of a flag with the given name set.

This method will return None if name is empty or doesn’t correspond to any named flag.

pub const fn is_empty(&self) -> bool

Whether all bits in self are unset.

pub const fn is_all(&self) -> bool

Whether all known bits in this flags value are set.

pub const fn intersects(&self, other: Self) -> bool

Whether any set bits in other are also set in self.

pub const fn contains(&self, other: Self) -> bool

Whether all set bits in other are also set in self.

pub fn insert(&mut self, other: Self)

The bitwise or (|) of the bits in self and other.

pub fn remove(&mut self, other: Self)

The intersection of self with the complement of other (&!).

This method is not equivalent to self & !other when other has unknown bits set. remove won’t truncate other, but the ! operator will.

pub fn toggle(&mut self, other: Self)

The bitwise exclusive-or (^) of the bits in self and other.

pub fn set(&mut self, other: Self, value: bool)

Call insert when value is true or remove when value is false.

pub const fn intersection(self, other: Self) -> Self

The bitwise and (&) of the bits in self and other.

pub const fn union(self, other: Self) -> Self

The bitwise or (|) of the bits in self and other.

pub const fn difference(self, other: Self) -> Self

The intersection of self with the complement of other (&!).

This method is not equivalent to self & !other when other has unknown bits set. difference won’t truncate other, but the ! operator will.

pub const fn symmetric_difference(self, other: Self) -> Self

The bitwise exclusive-or (^) of the bits in self and other.

pub const fn complement(self) -> Self

The bitwise negation (!) of the bits in self, truncating the result.

impl SqliteFunctionBehavior

pub const fn iter(&self) -> Iter<SqliteFunctionBehavior>

Yield a set of contained flags values.

Each yielded flags value will correspond to a defined named flag. Any unknown bits will be yielded together as a final flags value.

pub const fn iter_names(&self) -> IterNames<SqliteFunctionBehavior>

Yield a set of contained named flags values.

This method is like iter, except only yields bits in contained named flags. Any unknown bits, or bits not corresponding to a contained flag will not be yielded.

Trait Implementations

impl Binary for SqliteFunctionBehavior

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

Formats the value using the given formatter.

impl BitAnd for SqliteFunctionBehavior

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

The bitwise and (&) of the bits in self and other.

type Output = SqliteFunctionBehavior

The resulting type after applying the & operator.

impl BitAndAssign for SqliteFunctionBehavior

fn bitand_assign(&mut self, other: Self)

The bitwise and (&) of the bits in self and other.

impl BitOr for SqliteFunctionBehavior

fn bitor(self, other: SqliteFunctionBehavior) -> Self

The bitwise or (|) of the bits in self and other.

type Output = SqliteFunctionBehavior

The resulting type after applying the | operator.

impl BitOrAssign for SqliteFunctionBehavior

fn bitor_assign(&mut self, other: Self)

The bitwise or (|) of the bits in self and other.

impl BitXor for SqliteFunctionBehavior

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

The bitwise exclusive-or (^) of the bits in self and other.

type Output = SqliteFunctionBehavior

The resulting type after applying the ^ operator.

impl BitXorAssign for SqliteFunctionBehavior

fn bitxor_assign(&mut self, other: Self)

The bitwise exclusive-or (^) of the bits in self and other.

impl Clone for SqliteFunctionBehavior

fn clone(&self) -> SqliteFunctionBehavior

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for SqliteFunctionBehavior

impl Debug for SqliteFunctionBehavior

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

Formats the value using the given formatter.

impl Default for SqliteFunctionBehavior

fn default() -> Self

Returns Self::empty()

impl Eq for SqliteFunctionBehavior

impl Extend<SqliteFunctionBehavior> for SqliteFunctionBehavior

fn extend<T: IntoIterator<Item = Self>>(&mut self, iterator: T)

The bitwise or (|) of the bits in each flags value.

fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl Flags for SqliteFunctionBehavior

const FLAGS: &'static [Flag<SqliteFunctionBehavior>]

The set of defined flags.

type Bits = i32

The underlying bits type.

fn bits(&self) -> i32

Get the underlying bits value.

fn from_bits_retain(bits: i32) -> SqliteFunctionBehavior

Convert from a bits value exactly.

fn all_named() -> SqliteFunctionBehavior

Get a flags value with all bits from named flags set.

fn empty() -> Self

Get a flags value with all bits unset.

fn all() -> Self

Get a flags value with all known bits set.

fn known_bits(&self) -> Self::Bits

Get the known bits from a flags value.

fn unknown_bits(&self) -> Self::Bits

Get the unknown bits from a flags value.

fn contains_unknown_bits(&self) -> bool

This method will return true if any unknown bits are set.

fn from_bits(bits: Self::Bits) -> Option<Self>

Convert from a bits value.

fn from_bits_truncate(bits: Self::Bits) -> Self

Convert from a bits value, unsetting any unknown bits.

fn from_name(name: &str) -> Option<Self>

Get a flags value with the bits of a flag with the given name set.

fn iter(&self) -> Iter<Self>

Yield a set of contained flags values.

fn iter_names(&self) -> IterNames<Self>

Yield a set of contained named flags values.

fn iter_defined_names() -> IterDefinedNames<Self>

Yield a set of all named flags defined by Self::FLAGS.

fn iter_equal_names(&self) -> IterEqualNames<Self>

Get an iterator over all defined names for this flags value.

fn is_empty(&self) -> bool

Whether all bits in this flags value are unset.

fn is_all(&self) -> bool

Whether all known bits in this flags value are set.

fn intersects(&self, other: Self) -> bool

where Self: Sized,

Whether any set bits in other are also set in self.

fn contains(&self, other: Self) -> bool

where Self: Sized,

Whether all set bits in other are also set in self.

fn truncate(&mut self)

where Self: Sized,

Remove any unknown bits from the flags.

fn insert(&mut self, other: Self)

where Self: Sized,

The bitwise or (|) of the bits in self and other.

fn remove(&mut self, other: Self)

where Self: Sized,

The intersection of self with the complement of other (&!).

fn toggle(&mut self, other: Self)

where Self: Sized,

The bitwise exclusive-or (^) of the bits in self and other.

fn set(&mut self, other: Self, value: bool)

where Self: Sized,

Call Flags::insert when value is true or Flags::remove when value is false.

fn clear(&mut self)

where Self: Sized,

Unsets all bits in the flags.

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

The bitwise and (&) of the bits in self and other.

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

The bitwise or (|) of the bits in self and other.

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

The intersection of self with the complement of other (&!).

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

The bitwise exclusive-or (^) of the bits in self and other.

fn complement(self) -> Self

The bitwise negation (!) of the bits in self, truncating the result.

impl FromIterator<SqliteFunctionBehavior> for SqliteFunctionBehavior

fn from_iter<T: IntoIterator<Item = Self>>(iterator: T) -> Self

The bitwise or (|) of the bits in each flags value.

impl Hash for SqliteFunctionBehavior

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

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 IntoIterator for SqliteFunctionBehavior

type Item = SqliteFunctionBehavior

The type of the elements being iterated over.

type IntoIter = Iter<SqliteFunctionBehavior>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl LowerHex for SqliteFunctionBehavior

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

Formats the value using the given formatter.

impl Not for SqliteFunctionBehavior

fn not(self) -> Self

The bitwise negation (!) of the bits in self, truncating the result.

type Output = SqliteFunctionBehavior

The resulting type after applying the ! operator.

impl Octal for SqliteFunctionBehavior

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

Formats the value using the given formatter.

impl PartialEq for SqliteFunctionBehavior

fn eq(&self, other: &SqliteFunctionBehavior) -> 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 PublicFlags for SqliteFunctionBehavior

type Primitive = i32

The type of the underlying storage.

type Internal = InternalBitFlags

The type of the internal field on the generated flags type.

impl StructuralPartialEq for SqliteFunctionBehavior

impl Sub for SqliteFunctionBehavior

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

The intersection of self with the complement of other (&!).

This method is not equivalent to self & !other when other has unknown bits set. difference won’t truncate other, but the ! operator will.

type Output = SqliteFunctionBehavior

The resulting type after applying the - operator.

impl SubAssign for SqliteFunctionBehavior

fn sub_assign(&mut self, other: Self)

The intersection of self with the complement of other (&!).

This method is not equivalent to self & !other when other has unknown bits set. difference won’t truncate other, but the ! operator will.

impl UpperHex for SqliteFunctionBehavior

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

Formats the value using the given formatter.