# Common Parameters in Sink `URI` for `TiDB` and `MySQL`

+ **`tidb://[userinfo@][host]:[port][/path]?[parameters]`**
+ **`mysql://[userinfo@][host]:[port][/path]?[parameters]`**

| Parameter             | Parameter Value                                                                     |
| :-------------------- | :---------------------------------------------------------------------------------- |
| worker-count          | default is 16                                                                       |
| max-txn-row           | default is 256                                                                      |
| time-zone             | default is the timezone of `TiCDC` process, set to empty to use downstream timezone |
| transaction-atomicity | `table` or `none`, default is `table`                                               |

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`worker-count`: The number of `SQL` statements that can be concurrently executed to the downstream (optional, 16 by default)

`max-txn-row`: The size of a transaction batch that can be executed to the downstream (optional, 256 by default)

`time-zone`: The time zone used when connecting to the downstream `MySQL` instance, which is effective since `v4.0.8`. This is an optional parameter. If this parameter is not specified, the time zone of `TiCDC` service processes is used. If this parameter is set to an empty value, no time zone is specified when `TiCDC` connects to the downstream `MySQL` instance and the default time zone of the downstream is used.

`transaction-atomicity`: The atomicity level of a transaction. This is an optional parameter, with the default value of table. When the value is table, `TiCDC` ensures the atomicity of a single-table transaction. When the value is none, `TiCDC` splits the single-table transaction.

For parameters in sink `URI` with `kafka`, please refer to `https://docs.pingcap.com/tidb/stable/manage-ticdc` for details.