Bug Description

Users cannot create table columns whose names start with "index" (e.g., index, index_id, indexed_value) because the declaration parser misclassifies them as index declarations.

Root Cause

In src/datajoint/declare.py:373, the regex pattern used to detect index declarations is overly permissive:

elif re.match(r"^(unique\s+)?index\s*.*$", line, re.I):  # index
    compile_index(line, index_sql, adapter)

This matches any line starting with "index", not just actual index declarations like index(col1, col2).

Steps to Reproduce

import datajoint as dj

schema = dj.Schema("test")

@schema
class MyTable(dj.Manual):
    definition = """
    index_id : int
    ---
    index_value : float
    """

This raises a DataJointError because index_id : int gets matched by the regex and routed to compile_index() instead of compile_attribute().

Affected Attribute Names

Any attribute starting with "index" (case-insensitive): index, index_id, indexed_value, INDEX_SOMETHING, etc.

Proposed Fix

Change the regex to require parentheses, matching only actual index declarations:

elif re.match(r"^(unique\s+)?index\s*\(.*\)$", line, re.I):  # index

Note: compile_index() itself already uses a more restrictive regex that requires parentheses ((?P<unique>unique\s+)?index\s*\(\s*(?P<args>.*)\)), confirming this is the correct fix.

Existing Test

tests/integration/test_declare.py::test_regex_mismatch already documents this failure by expecting the error — it should be updated to expect success after the fix.