## TL;DR

The two vectors in VEC_L2_DISTANCE, VEC_COSINE_DISTANCE, and the other vector functions must have the same dimension, otherwise an error is returned, for example ERROR 1105 (HY000): vectors have different dimensions.

## The error

```text
ERROR 1105 vectors have different dimensions
```

## Fix

1. The two vectors in VEC_L2_DISTANCE, VEC_COSINE_DISTANCE, and the other vector functions must have the same dimension, otherwise an error is returned, for example ERROR 1105 (HY000): vectors have different dimensions.
   Expected: you can confirm this matches your situation.
2. Re-run the original operation and confirm the error is gone.
   Expected: no error, normal output.

## When to use

- You hit this exact error with TiDB.
- The symptom matches: ERROR 1105 vectors have different dimensions.

## When NOT to use

- A different error message from TiDB; the cause here is specific to this error.
- Unrelated TiDB issues (different feature, different failure).
- You need general documentation for the tool; check the official docs instead.

## Compatibility

Reported against TiDB. Source: https://docs-archive.pingcap.com/tidb/v8.4/vector-search-data-types/.

## Variant phrasings

### ERROR 1105 vectors have different dimensions

## Why it happens

Vector functions require both operands to have the same dimension. A mismatch is a hard error, not a silent cast.

## Edge cases

- If your error message differs even slightly, this is probably a different issue; search the exact text.
- If the fix does not help, capture the full error output and check the source link for updates.

## Source

https://docs-archive.pingcap.com/tidb/v8.4/vector-search-data-types/