> ## Documentation Index
> Fetch the complete documentation index at: https://docs.risingwave.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Query MySQL tables (non-CDC)

> Fetch data from MySQL tables on demand via the mysql_query table-valued function (non-CDC).

RisingWave allows you to query MySQL tables directly with the `mysql_query` table-valued function (TVF). It offers a simpler alternative to Change Data Capture (CDC) when working with MySQL data in RisingWave.

Unlike CDC, which continuously syncs data changes, this function lets you fetch data directly from MySQL when needed. Therefore, this approach is ideal for static or infrequently updated data, as it's more resource-efficient than maintaining a constant CDC connection.

<Note>
  **Not CDC.** This approach fetches rows on demand via a table-valued function. For continuous change replication, use [MySQL CDC](/ingestion/sources/mysql/mysql-cdc).
</Note>

<Note>
  Added in v2.2.0.
</Note>

## Syntax

Define `mysql_query` as follows:

```sql theme={null}
mysql_query(
    hostname varchar,      -- Database hostname
    port varchar,          -- Database port
    username varchar,      -- Authentication username
    password varchar,      -- Authentication password
    database_name varchar, -- Target database name
    query varchar          -- SQL query to execute
)
```

## Data type mapping

The following table shows how MySQL data types are mapped to RisingWave data types:

| MySQL Type       | RisingWave Type |
| :--------------- | :-------------- |
| `bit(1)`         | `boolean`       |
| `bit(>1)`        | `bytea`         |
| `bool`/`boolean` | `smallint`      |
| `tinyint`        | `smallint`      |
| `smallint`       | `smallint`      |
| `mediumint`      | `int`           |
| `int`            | `int`           |
| `bigint`         | `bigint`        |
| `float`          | `float32`       |
| `double`         | `float64`       |
| `decimal`        | `decimal`       |
| `numeric`        | `decimal`       |
| `year`           | `int`           |
| `date`           | `date`          |
| `time`           | `time`          |
| `datetime`       | `timestamp`     |
| `timestamp`      | `timestamptz`   |
| `varchar`        | `varchar`       |
| `char`           | `varchar`       |
| `json`           | `jsonb`         |
| `blob`           | `bytea`         |
| `tinyblob`       | `bytea`         |
| `mediumblob`     | `bytea`         |
| `longblob`       | `bytea`         |
| `array`          | *unsupported*   |
| `enum`           | *unsupported*   |
| `set`            | *unsupported*   |
| `geometry`       | *unsupported*   |
| `null`           | *unsupported*   |

## Example

1. In your MySQL database, create a table and populate it with sample data of various data types.

```sql theme={null}
CREATE TABLE test (
    id bigint primary key, v0 bit, v1 bool, v2 tinyint(1),
    v3 tinyint(2), v4 smallint, v5 mediumint, v6 integer,
    v7 bigint, v8 float, v9 double, v10 numeric(4, 2),
    v11 decimal(4, 2), v12 char(255), v13 varchar(255),
    v14 bit(10), v15 tinyblob, v16 blob, v17 mediumblob,
    v18 longblob, v19 date, v20 time, v21 timestamp,
    v22 json
);

INSERT INTO test SELECT
    1 as id, true as v0, true as v1, 2 as v2, 3 as v3, 4 as v4, 5 as v5,
    6 as v6, 7 as v7, 1.08 as v8, 1.09 as v9, 1.10 as v10, 1.11 as v11,
    'char' as v12, 'varchar' as v13, b'1010' as v14, x'16' as v15, x'17' as v16,
    x'18' as v17, x'19' as v18, '2021-01-01' as v19, '12:34:56' as v20,
    '2021-01-01 12:34:56' as v21, JSON_OBJECT('key1', 1, 'key2', 'abc');
```

2. In RisingWave, use `mysql_query` function to perform the query.

```sql theme={null}
SELECT * 
FROM mysql_query('$MYSQL_HOST', '$MYSQL_TCP_PORT', '$RISEDEV_MYSQL_USER', '$MYSQL_PWD', 'tvf', 'select * from test;');
----RESULT
1 t 1 2 3 4 5 6 7 1.08 1.09 1.10 1.11 char varchar \x000a \x16 \x17 \x18 \x19 2021-01-01 12:34:56 2021-01-01 12:34:56+00:00 {"key1": 1, "key2": "abc"}
```