Introduction

The Redshift COPY error about a delimiter not being found usually means the input file does not match the format described in your COPY statement. Redshift expected to split each row into columns using a specific delimiter, but the data line did not contain that delimiter where Redshift expected it.

This is almost always a file-format mismatch rather than a problem with Redshift itself. The fix is to compare the actual file contents with the COPY options you provided, especially DELIMITER, CSV, QUOTE, ESCAPE, and the expected column count.

Start By Inspecting The Real File Format

Do not assume a file is a normal comma-separated CSV just because it has a .csv name. Look at a few raw lines from the source file and confirm the exact separator, quote character, header behavior, and line endings.

For a standard pipe-delimited file, the COPY command might look like this:

1COPY sales
2FROM 's3://my-bucket/import/sales.txt'
3IAM_ROLE 'arn:aws:iam::123456789012:role/redshift-copy-role'
4DELIMITER '|'
5IGNOREHEADER 1
6REGION 'us-east-1';

If the file is truly CSV with quoted fields, prefer the CSV option instead of manually describing comma behavior:

1COPY sales
2FROM 's3://my-bucket/import/sales.csv'
3IAM_ROLE 'arn:aws:iam::123456789012:role/redshift-copy-role'
4CSV
5IGNOREHEADER 1
6REGION 'us-east-1';

That tells Redshift to handle common CSV rules, including quoted commas, more safely than a plain DELIMITER ',' approach.

Watch For Quoted Delimiters And Embedded Characters

A very common cause of this error is a data file that contains delimiters inside quoted text. If you load such a file as a simple delimited text file, Redshift sees too many or too few separators and reports parsing failures.

For example, this row is valid CSV:

1,"Alice, Smith",42

If you load it with a naive delimiter rule instead of CSV, Redshift may interpret the comma inside the quoted name as a real column separator. The same problem appears with tabs, pipes, and escape sequences if the file generation process and the COPY options disagree.

Use Load Error Tables To See The Failing Row

Redshift stores load diagnostics that are far more useful than guessing from the top-level error alone. After a failed COPY, inspect the load error tables to see which row and column caused the issue.

1SELECT filename, line_number, colname, err_reason
2FROM stl_load_errors
3ORDER BY starttime DESC
4LIMIT 20;

That query often reveals whether the actual issue is a wrong delimiter, an unexpected quote, a header row that was not skipped, or a row with too few fields. It is one of the fastest ways to stop guessing.

Check Column Count And Header Handling

Sometimes the delimiter is correct, but the file still fails because the row shape does not match the target table. If the table expects eight columns and a row produces only seven after splitting, Redshift surfaces a delimiter-related parsing error even though the root cause might be missing data.

Headers are another frequent source of trouble. If the first row contains column names and you forget IGNOREHEADER 1, Redshift tries to parse the header as data and the error message can point you in the wrong direction.

Clean The File Or Adjust The COPY Options

Once you know the actual problem, choose one side to normalize. Either fix the exported file so it matches a clean format, or adjust the COPY options so they match the file generator. The cleaner long-term approach is usually to standardize the export format rather than piling more options onto the load command.

If you are dealing with messy source data, isolate a small sample file that reproduces the error and get that working first. Redshift load problems are much easier to reason about when you are testing ten lines instead of ten million.

Common Pitfalls

The most common mistake is using DELIMITER ',' on a real CSV file that contains quoted commas, when CSV is the safer option. Another is trusting the file extension instead of inspecting the raw data. Developers also forget to skip headers or overlook Windows line endings, which can make otherwise valid files fail in confusing ways. Finally, do not diagnose from the main error message alone. stl_load_errors is usually where the real answer lives.

Summary

• A delimiter-not-found error usually means the COPY options do not match the actual file format.
• Inspect the raw file and confirm delimiter, quotes, headers, and line endings.
• Use CSV for true CSV files, especially when quoted delimiters are possible.
• Query stl_load_errors to see the failing row and reason.
• Standardize the export format when possible instead of layering on fragile parsing options.