What causes COPY INTO Date/Timestamp Conversion Error?

File contains dates in a non-ISO format (e.g. 'MM/DD/YYYY') but the target table expects ISO 8601. File format's DATE_FORMAT or TIMESTAMP_FORMAT parameter not set to match the source data. Mixed date formats within the same file column. Timezone offset present in some values but not others. Source system changed its date serialisation format after a software update

How do I fix COPY INTO Date/Timestamp Conversion Error?

Inspect the raw file: `SELECT $1 FROM @stage/file.csv LIMIT 10` to see the actual date format. Update the file format object: `ALTER FILE FORMAT SET DATE_FORMAT = 'MM/DD/YYYY'`. Use a SELECT transformation in COPY INTO with TO_DATE() or TRY_TO_DATE() to handle conversion explicitly. Set `ON_ERROR = CONTINUE` temporarily to load valid rows and identify the format of failing values. If mixed formats exist, load the column as VARCHAR and convert it in a downstream transformation step

High severitydata loading

Power BI Refresh Error:
COPY INTO Date/Timestamp Conversion Error

What does this error mean?

A COPY INTO command failed because a value in the source file could not be converted to the target DATE, TIME, or TIMESTAMP column type. The date/time format in the file does not match the expected format.

Common causes

1File contains dates in a non-ISO format (e.g. 'MM/DD/YYYY') but the target table expects ISO 8601
2File format's DATE_FORMAT or TIMESTAMP_FORMAT parameter not set to match the source data
3Mixed date formats within the same file column
4Timezone offset present in some values but not others
5Source system changed its date serialisation format after a software update

How to fix it

1Inspect the raw file: `SELECT $1 FROM @stage/file.csv LIMIT 10` to see the actual date format
2Update the file format object: `ALTER FILE FORMAT <fmt> SET DATE_FORMAT = 'MM/DD/YYYY'`
3Use a SELECT transformation in COPY INTO with TO_DATE() or TRY_TO_DATE() to handle conversion explicitly
4Set `ON_ERROR = CONTINUE` temporarily to load valid rows and identify the format of failing values
5If mixed formats exist, load the column as VARCHAR and convert it in a downstream transformation step

Frequently asked questions

What is the default date format expected by Snowflake COPY INTO?

By default Snowflake expects ISO 8601 format: YYYY-MM-DD for dates and YYYY-MM-DDTHH:MI:SS for timestamps. Override with the DATE_FORMAT or TIMESTAMP_FORMAT file format options.