wehub-resource-sync
69 lines
2.6 KiB
Markdown
69 lines
2.6 KiB
Markdown
## 🎉 Added support for `UNIQUE` constraints in PostgreSQL, MySQL, SQLite
|
|
|
|
For PostgreSQL, unique constraints can be defined at the column level for single-column constraints, and in the third parameter for multi-column constraints. In both cases, it will be possible to define a custom name for the constraint. Additionally, PostgreSQL will receive the `NULLS NOT DISTINCT` option to restrict having more than one NULL value in a table. [Reference](https://www.postgresql.org/docs/current/ddl-constraints.html#DDL-CONSTRAINTS-UNIQUE-CONSTRAINTS)
|
|
|
|
Examples that just shows a different `unique` usage. Please don't search a real usage for those tables
|
|
|
|
```ts
|
|
// single column
|
|
const table = pgTable('table', {
|
|
id: serial('id').primaryKey(),
|
|
name: text('name').notNull().unique(),
|
|
state: char('state', { length: 2 }).unique('custom'),
|
|
field: char('field', { length: 2 }).unique('custom_field', { nulls: 'not distinct' }),
|
|
});
|
|
// multiple columns
|
|
const table = pgTable('table', {
|
|
id: serial('id').primaryKey(),
|
|
name: text('name').notNull(),
|
|
state: char('state', { length: 2 }),
|
|
}, (t) => ({
|
|
first: unique('custom_name').on(t.name, t.state).nullsNotDistinct(),
|
|
second: unique('custom_name1').on(t.name, t.state),
|
|
}));
|
|
```
|
|
|
|
For MySQL, everything will be the same except for the `NULLS NOT DISTINCT` option. It appears that MySQL does not support it
|
|
|
|
Examples that just shows a different `unique` usage. Please don't search a real usage for those tables
|
|
|
|
```ts
|
|
// single column
|
|
const table = mysqlTable('table', {
|
|
id: serial('id').primaryKey(),
|
|
name: text('name').notNull().unique(),
|
|
state: text('state').unique('custom'),
|
|
field: text('field').unique('custom_field'),
|
|
});
|
|
// multiple columns
|
|
const table = mysqlTable('cities1', {
|
|
id: serial('id').primaryKey(),
|
|
name: text('name').notNull(),
|
|
state: text('state'),
|
|
}, (t) => ({
|
|
first: unique().on(t.name, t.state),
|
|
second: unique('custom_name1').on(t.name, t.state),
|
|
}));
|
|
```
|
|
|
|
In SQLite unique constraints are the same as unique indexes. As long as you can specify a name for the unique index in SQLite - we will treat all unique constraints as unique indexes in internal implementation
|
|
|
|
```ts
|
|
// single column
|
|
const table = sqliteTable('table', {
|
|
id: int('id').primaryKey(),
|
|
name: text('name').notNull().unique(),
|
|
state: text('state').unique('custom'),
|
|
field: text('field').unique(),
|
|
});
|
|
// multiple columns
|
|
const table = sqliteTable('table', {
|
|
id: int('id').primaryKey(),
|
|
name: text('name').notNull(),
|
|
state: text('state'),
|
|
}, (t) => ({
|
|
first: unique().on(t.name, t.state),
|
|
second: unique('custom').on(t.name, t.state),
|
|
}));
|
|
```
|