# S01018 {#s01018}

## Error Code {#error_code .section}

S01018

## Error Message {#error_message .section}

`A STRING or SYMBOL column used for value-partitioning cannot contain invisible characters. RefId:S01018`

## Probable Causes {#probable_causes .section}

When writing or upserting data to a VALUE-partitioned database, only visible characters from the ASCII character set are allowed for the partitioning columns. If data in a partitioning column contains invisible characters \(ASCII 0-32 and 127\), such as \\n, \\t, and spaces, this error is thrown.

## Solutions {#solutions .section}

Check if the data being written or updated in the partitioning column contains invisible characters. If so, remove the invisible characters and try again.

**Parent topic:**[Error Code Reference](../../Troubleshooting/ErrorCode.md)

