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 advisor drafts CREATE INDEX from columns that appear in filters and sorts, and says to confirm selectivity. The covering-index builder lists equality columns before a range or sort column. SQL Server and PostgreSQL accept INCLUDE. MySQL has no INCLUDE, so an extra column goes on the key list if you need it there. The size estimator multiplies rows by key bytes plus about eight bytes, plus about fifteen percent. Measure that on a copy.
Do not create the index during the reading. A suggested index is a sketch. Extra columns make the index larger.
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 suggested columns.
- Read INCLUDE against the engine.
- Write the size estimate as an estimate.
- Do not create the index.
- Stop.
Mistakes that outlive the statement
Indexing Strategies goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- The index created during the reading.
- INCLUDE pasted onto MySQL.
- The estimate treated as a measured size.
- A duplicate of an index you already have.
Decisions to write down
One decision for Indexing Strategies: The columns are written. The engine is written. Nothing was created. And selectivity is still to be checked.
Checks before you call it done
Confirm this before you call the change done: The query is written. The column order is written. The size is labeled an estimate. Nothing was created. And the database is yours. If one of those fails, stop.
-- Equality columns before a range column.
-- MySQL has no INCLUDE.
-- Do not create the index during the reading.Before you leave the database
Indexing Strategies 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.
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