This is an original planning guide. It is not a vendor manual, an official standard, or legal advice. Example addresses use documentation ranges. Review every command before you paste it.
What this hour is for
The anti-pattern list can mention SELECT *, a leading wildcard, OR across columns, an UPDATE or DELETE without WHERE, or a comma join. If none match, it says so. The sargability check can mention a function wrapped around a column, a LIKE that starts with a wildcard, OR, or arithmetic on a column. If none of those appear, the result is no starter sargability note, and you still check the real plan. The comparer subtracts two millisecond numbers you type and asks for the same data and the same cache. It does not run the query.
Do not rewrite production SQL during the reading. A note is a hint. An empty sargability note is a valid result.
192.0.2.10, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are documentation. example.com is a documentation name. A sample password is replaced. It is not a password you keep.
The change you can finish
Apply nothing while you are writing the note. When the lab window opens, it is one change on the database named in the ticket. Read the draft, then the database, then decide.
Rollback is the backup, the file, or the snapshot you saved first. You do not invent a rollback after the only copy is gone.
- Paste one query.
- Read the anti-pattern notes.
- Read the sargability notes.
- Type two timings you already measured.
- Do not rewrite the statement.
- Stop.
Mistakes that outlive the statement
Query Optimization Tips goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- Production SQL rewritten during the reading.
- An empty sargability note treated as a failure.
- Timings compared from different data.
- The query run from the page.
Decisions to write down
One decision for Query Optimization Tips: The notes were read. The timings match. Nothing was rewritten. And the database is yours.
Checks before you call it done
Confirm this before you call the change done: The query is written. The notes are written. The timings are written. Nothing was rewritten. And the database is yours. If one of those fails, stop.
Before you leave the database
Query Optimization Tips ends when the database in the prompt is the database in the ticket. If it is not, you are on the wrong database. Stop.
The draft stays a draft until a person has read the names in it. A generator does not log into the database. You delete a line that names a host, a database, or an account you did not write down.
192.0.2.10, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are documentation. example.com is a documentation name. They belong in the note. They are not values you leave on a database because a draft included them.
prompt-for-this is a reminder that a secret is missing. It is not a password, a key, or a token you save in the ticket or in git. A sample password in a draft is replaced. It is not a password you keep.
One change is the window. If two things move and the result is wrong, you will not know which one did it.
If the same step fails twice, stop for the day. Restore the copy you took first.
A second person reads the database name and the change aloud. If they cannot find them in the ticket, the note is not done.
This page is a planning guide. It is not a vendor manual, not an official standard, and not permission to touch a database you do not administer. You do not disable authentication, a firewall, or TLS to make a check pass.
Tools for this guide
These tools run in the browser on this site. They do not log into your machines.
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