AlterTable¶

AlterTable handles SQL ALTER TABLE statements. Its default methods use Store and StoreMut. Override them for storage-specific schema changes, such as updating secondary indexes.

It provides four methods:

1. rename_schema: Corresponds to the SQL statement ALTER TABLE {table-name} RENAME TO {other-name};. This method renames a schema.

2. rename_column: Corresponds to the SQL statement ALTER TABLE {table-name} RENAME COLUMN {col1} TO {col2};. This method renames a column within a table.

3. add_column: Corresponds to the SQL statement ALTER TABLE {table-name} ADD COLUMN {col} {data-type} {constraints}. This method adds a new column to a table with specified data type and constraints.

4. drop_column: Corresponds to the SQL statement ALTER TABLE {table-name} DROP COLUMN {col}. This method removes a column from a table.

pub trait AlterTable: Store + StoreMut {
    fn rename_schema(&mut self, table_name: &str, new_table_name: &str) -> Result<()>;

    fn rename_column(
        &mut self,
        table_name: &str,
        old_column_name: &str,
        new_column_name: &str,
    ) -> Result<()>;

    fn add_column(&mut self, table_name: &str, column_def: &ColumnDef) -> Result<()>;

    fn drop_column(
        &mut self,
        table_name: &str,
        column_name: &str,
        if_exists: bool,
    ) -> Result<()>;
}