Struct Update 

pub struct Update<T, F: Format<S, B>, S, B> { /* private fields */ }

Builder for an update operation, parameterized by the format type F and value types S, B.

Implementations

impl<T, F: Format<S, B>, S: Clone, B: Clone> Update<T, F, S, B>

pub fn values(&self) -> &[(F::Old, Option<Value<S, B>>)]

Returns a reference to the (old, new) value pairs.

pub fn extract_pk(&self) -> Vec<Value<S, B>>

where T: SchemaWithPK,

Extract the primary key values from this update’s values.

impl<T: DynTable, S: Clone + Debug + AsRef<str>, B: Clone + Debug + AsRef<[u8]>> Update<T, ChangesetFormat, S, B>

pub fn set( self, col_idx: usize, old: impl Into<Value<S, B>>, new: impl Into<Value<S, B>>, ) -> Result<Self, Error>

Sets the value for a specific column by index.

Arguments

• col_idx - The index of the column to set.
• old - The old value for the column.
• new - The new value for the column.

Errors

• ColumnIndexOutOfBounds - If the provided column index is out of bounds for the table schema.

pub fn set_new( self, col_idx: usize, new: impl Into<Value<S, B>>, ) -> Result<Self, Error>

Sets only the new value for a column, leaving old as undefined.

This is useful when the old value is not known (e.g., when parsing SQL UPDATE statements where only the new value is specified).

Arguments

• col_idx - The index of the column to set.
• new - The new value for the column.

Errors

• ColumnIndexOutOfBounds - If the column index is out of bounds.

Example

use sqlite_diff_rs::{Update, ChangesetFormat, TableSchema};

// CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT, age INTEGER)
let schema: TableSchema<String> = TableSchema::new("users".into(), 3, vec![1, 0, 0]);

// UPDATE users SET name = 'Bob' WHERE id = 1
// We know id=1 (PK, unchanged) and name='Bob' (new), but not the old name
let update = Update::<_, ChangesetFormat, String, Vec<u8>>::from(schema)
    .set(0, 1i64, 1i64).unwrap()      // PK: old=1, new=1 (unchanged)
    .set_new(1, "Bob").unwrap();      // name: old=undefined, new="Bob"

pub fn set_null(self, col_idx: usize) -> Result<Self, Error>

where S: Default, B: Default,

Sets a column to NULL for both old and new values.

Errors

• ColumnIndexOutOfBounds - If the column index is out of bounds for the table schema.

Example

use sqlite_diff_rs::{Update, ChangesetFormat, TableSchema};

// CREATE TABLE items (id INTEGER PRIMARY KEY, description TEXT)
let schema: TableSchema<String> = TableSchema::new("items".into(), 2, vec![1, 0]);

// UPDATE items SET description = NULL WHERE id = 1 AND description = NULL
let update = Update::<_, ChangesetFormat, String, Vec<u8>>::from(schema)
    .set(0, 1i64, 1i64).unwrap()
    .set_null(1).unwrap();

impl<T: DynTable, S: AsRef<str>, B: AsRef<[u8]>> Update<T, PatchsetFormat, S, B>

pub fn set( self, col_idx: usize, new: impl Into<Value<S, B>>, ) -> Result<Self, Error>

Sets the value for a specific column by index.

Implementation Note

In the patchset format, the old value is not stored for updates, so we set it to the default value of (). Only the new value is stored.

Arguments

• col_idx - The index of the column to set.
• new - The new value for the column.

Errors

• ColumnIndexOutOfBounds - If the provided column index is out of bounds for the table schema.

pub fn set_null(self, col_idx: usize) -> Result<Self, Error>

where S: Default, B: Default,

Sets a column to NULL.

Errors

• ColumnIndexOutOfBounds - If the column index is out of bounds for the table schema.

Example

use sqlite_diff_rs::{Update, PatchsetFormat, TableSchema};

// CREATE TABLE items (id INTEGER PRIMARY KEY, description TEXT)
let schema: TableSchema<String> = TableSchema::new("items".into(), 2, vec![1, 0]);

// UPDATE items SET description = NULL WHERE id = 1
let update = Update::<_, PatchsetFormat, String, Vec<u8>>::from(schema)
    .set(0, 1i64).unwrap()
    .set_null(1).unwrap();

Trait Implementations

impl<T, F: Format<S, B>, S, B> AsRef<T> for Update<T, F, S, B>

fn as_ref(&self) -> &T

Converts this type into a shared reference of the (usually inferred) input type.

impl<T: Clone, F: Clone + Format<S, B>, S: Clone, B: Clone> Clone for Update<T, F, S, B>

where F::Old: Clone,

fn clone(&self) -> Update<T, F, S, B>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Debug, F: Debug + Format<S, B>, S: Debug, B: Debug> Debug for Update<T, F, S, B>

where F::Old: Debug,

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

Formats the value using the given formatter.

impl<T: DynTable + Eq, F: Format<S, B>, S: Eq + AsRef<str>, B: Eq + AsRef<[u8]>> Eq for Update<T, F, S, B>

where F::Old: Eq,

impl<T: DynTable, F: Format<S, B>, S: Clone + AsRef<str>, B: Clone + AsRef<[u8]>> From<T> for Update<T, F, S, B>

where F::Old: Clone,

fn from(table: T) -> Self

Converts to this type from the input type.

impl<T: DynTable, F: Format<S, B>, S: AsRef<str>, B: AsRef<[u8]>> From<Update<T, F, S, B>> for Vec<(F::Old, Option<Value<S, B>>)>

fn from(update: Update<T, F, S, B>) -> Self

Converts to this type from the input type.

impl<T, F: Format<S, B>, S, B> Indirect for Update<T, F, S, B>

fn indirect(self, indirect: bool) -> Self

Mark this operation as indirect (trigger-induced or cascading).

impl<T: DynTable + PartialEq, F: Format<S, B>, S: PartialEq + AsRef<str>, B: PartialEq + AsRef<[u8]>> PartialEq for Update<T, F, S, B>

where F::Old: PartialEq,

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

Equality operator ==.

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

Inequality operator !=.