What causes COPY INTO File Size Limit Exceeded?

A JSON document in the staged file exceeds 16 MB after parsing into a VARIANT column. A CSV row has a string value longer than the maximum VARCHAR(16777216) length. A deeply nested JSON array or object expands beyond the 16 MB VARIANT limit during COPY. Source data was not validated before staging and contains abnormally large records

How do I fix COPY INTO File Size Limit Exceeded?

Identify the oversized rows: use `VALIDATE( , JOB_ID=>' ')` to see which files and rows failed.. For VARIANT: pre-process large JSON documents to split or truncate oversized arrays/objects before staging.. Use the `STRIP_OUTER_ARRAY=TRUE` option in the file format if the JSON is a large outer array containing many smaller objects.. Set `ON_ERROR=SKIP_FILE` or `ON_ERROR=CONTINUE` in the COPY options to load valid rows and log the failures.. For VARCHAR: increase the column size in the target table or truncate long values in a staging step.

Medium severitydata source

Power BI Refresh Error:
COPY INTO File Size Limit Exceeded

What does this error mean?

A COPY INTO command failed because an individual data value exceeded Snowflake's per-row size limit. For VARIANT/OBJECT/ARRAY types, the limit is 16 MB per value. Large semi-structured documents or very wide rows cause this error.

Common causes

1A JSON document in the staged file exceeds 16 MB after parsing into a VARIANT column
2A CSV row has a string value longer than the maximum VARCHAR(16777216) length
3A deeply nested JSON array or object expands beyond the 16 MB VARIANT limit during COPY
4Source data was not validated before staging and contains abnormally large records

How to fix it

1Identify the oversized rows: use `VALIDATE(<table>, JOB_ID=>'<copy_job_id>')` to see which files and rows failed.
2For VARIANT: pre-process large JSON documents to split or truncate oversized arrays/objects before staging.
3Use the `STRIP_OUTER_ARRAY=TRUE` option in the file format if the JSON is a large outer array containing many smaller objects.
4Set `ON_ERROR=SKIP_FILE` or `ON_ERROR=CONTINUE` in the COPY options to load valid rows and log the failures.
5For VARCHAR: increase the column size in the target table or truncate long values in a staging step.

Frequently asked questions

Is the 16 MB limit per-file or per-row?

Per-row (per VARIANT value, specifically). File size is not directly limited by Snowflake — the 16 MB constraint applies to the parsed value that would be stored in a VARIANT column.