# CREATE TABLE

CREATE TABLE defines a table's columns, value contracts and constraints. A table stores rows until they are changed or deleted; it does not require a ClickHouse table engine declaration.

## Syntax

```text
CREATE [TEMP | TEMPORARY] TABLE [IF NOT EXISTS] [schema.]name
(
    column type [column_constraint ...],
    ...
    [, table_constraint ...]
)
[STRICT | WITHOUT ROWID]

CREATE TABLE name AS SELECT ...
```

`STRICT` and `WITHOUT ROWID` can be combined with a comma in either order. `CREATE VIRTUAL TABLE` and modules such as FTS5 are not supported.

## Columns and constraints

Native types validate values on writes and casts. SQL columns permit `NULL` unless declared `NOT NULL`.

Supported constraints include `PRIMARY KEY`, `UNIQUE`, `NOT NULL`, `CHECK`, `DEFAULT` and foreign keys. In an ordinary table, a column declared exactly `INTEGER PRIMARY KEY` aliases the row identifier; `AUTOINCREMENT` is supported. A native `UInt64 PRIMARY KEY` does not have that row-identifier alias contract.

Generated columns can be `VIRTUAL` or `STORED`. `CREATE TABLE AS SELECT` retains projected native declarations and copies values, but does not copy source constraints.

## Examples

### Typed columns and defaults

```sql
CREATE TABLE events
(
    id INTEGER PRIMARY KEY,
    kind String NOT NULL,
    amount Decimal(18, 2) DEFAULT '0.00'
);
INSERT INTO events(id, kind) VALUES (1, 'view');
```

```sql
SELECT id, kind, amount
FROM events
FORMAT csv;
```

```text
1,"view",0.00
```

### A generated value

```sql
CREATE TABLE order_lines
(
    id INTEGER PRIMARY KEY,
    quantity INTEGER CHECK (quantity > 0),
    unit_price INTEGER NOT NULL,
    total INTEGER GENERATED ALWAYS AS (quantity * unit_price) STORED
);
INSERT INTO order_lines(id, quantity, unit_price) VALUES (1, 3, 10);
```

```sql
SELECT id, total
FROM order_lines
FORMAT csv;
```

```text
1,30
```

### Creating a table from a query

```sql
CREATE TABLE selected_events AS
SELECT id, kind FROM events WHERE kind = 'view';
```

```sql
SELECT * FROM selected_events
FORMAT csv;
```

```text
1,"view"
```

See [data types](https://coordinatordb.com/docs/reference/data-types), [temporary tables](https://coordinatordb.com/docs/reference/statements/create/table/temporary-table) and [ALTER TABLE](https://coordinatordb.com/docs/reference/statements/alter).