Enum SchemaOperation 

pub enum SchemaOperation {
    CreateTable(TableInfo),
    DropTable(String),
    RenameTable {
        from: String,
        to: String,
    },
    AddColumn {
        table: String,
        column: ColumnInfo,
    },
    DropColumn {
        table: String,
        column: String,
        table_info: Option<TableInfo>,
    },
    AlterColumnType {
        table: String,
        column: String,
        from_type: String,
        to_type: String,
        table_info: Option<TableInfo>,
    },
    AlterColumnNullable {
        table: String,
        column: ColumnInfo,
        from_nullable: bool,
        to_nullable: bool,
        table_info: Option<TableInfo>,
    },
    AlterColumnDefault {
        table: String,
        column: String,
        from_default: Option<String>,
        to_default: Option<String>,
        table_info: Option<TableInfo>,
    },
    RenameColumn {
        table: String,
        from: String,
        to: String,
    },
    AddPrimaryKey {
        table: String,
        columns: Vec<String>,
        table_info: Option<TableInfo>,
    },
    DropPrimaryKey {
        table: String,
        table_info: Option<TableInfo>,
    },
    AddForeignKey {
        table: String,
        fk: ForeignKeyInfo,
        table_info: Option<TableInfo>,
    },
    DropForeignKey {
        table: String,
        name: String,
        table_info: Option<TableInfo>,
    },
    AddUnique {
        table: String,
        constraint: UniqueConstraintInfo,
        table_info: Option<TableInfo>,
    },
    DropUnique {
        table: String,
        name: String,
        table_info: Option<TableInfo>,
    },
    CreateIndex {
        table: String,
        index: IndexInfo,
    },
    DropIndex {
        table: String,
        name: String,
    },
}

A single schema modification operation.

Variants

CreateTable(TableInfo)

Create a new table.

DropTable(String)

Drop an existing table.

RenameTable

Rename a table.

Fields

from: String

to: String

AddColumn

Add a column to a table.

Fields

table: String

column: ColumnInfo

DropColumn

Drop a column from a table.

For SQLite, safely dropping a column on versions < 3.35 requires table recreation. When table_info is present, the SQLite DDL generator can emit a correct recreate-copy-drop sequence (preserving indexes we track).

Fields

table: String

column: String

table_info: Option<TableInfo>

AlterColumnType

Change a column’s type.

Fields

table: String

column: String

from_type: String

to_type: String

table_info: Option<TableInfo>

AlterColumnNullable

Change a column’s nullability.

Fields

table: String

column: ColumnInfo

from_nullable: bool

to_nullable: bool

table_info: Option<TableInfo>

AlterColumnDefault

Change a column’s default value.

Fields

table: String

column: String

from_default: Option<String>

to_default: Option<String>

table_info: Option<TableInfo>

RenameColumn

Rename a column.

Fields

table: String

from: String

to: String

AddPrimaryKey

Add a primary key constraint.

Fields

table: String

columns: Vec<String>

table_info: Option<TableInfo>

DropPrimaryKey

Drop a primary key constraint.

Fields

table: String

table_info: Option<TableInfo>

AddForeignKey

Add a foreign key constraint.

Fields

table: String

fk: ForeignKeyInfo

table_info: Option<TableInfo>

DropForeignKey

Drop a foreign key constraint.

Fields

table: String

name: String

table_info: Option<TableInfo>

AddUnique

Add a unique constraint.

Fields

table: String

constraint: UniqueConstraintInfo

table_info: Option<TableInfo>

DropUnique

Drop a unique constraint.

Fields

table: String

name: String

table_info: Option<TableInfo>

CreateIndex

Create an index.

Fields

table: String

index: IndexInfo

DropIndex

Drop an index.

Fields

table: String

name: String

Implementations

impl SchemaOperation

pub fn is_destructive(&self) -> bool

Check if this operation potentially loses data.

pub fn inverse(&self) -> Option<Self>

Get the inverse operation for rollback, if possible.

Some operations are not reversible (e.g., dropping a table/column) because the original schema and data cannot be reconstructed from the operation alone.

pub fn table(&self) -> Option<&str>

Get the table this operation affects.

Trait Implementations

impl Clone for SchemaOperation

fn clone(&self) -> SchemaOperation

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SchemaOperation

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

Formats the value using the given formatter.