Is There a Term for Database Operations That Don't Change Data?

Question

Is there a catch-all term for database operations that don't alter any data at all?

For example, SELECT statements have no effect on the contents of the database.

On the other hand, INSERT, UPDATE, and DELETE statements have the potential to create, edit, or remove data.

To clarify, I'm not referring to idempotent operations, which can be repeated multiple times without altering data more than once.

there's the term "nilpotent", but I'm not sure anyone will understand you. I'd stick to "query operation"s. — John Dvorak, Aug 14 '14 at 19:09
"Nondestructive" excludes `INSERT` which doesn't destroy anything? — Chris Schiffhauer, Aug 14 '14 at 19:49
read-only? or just SELECT. In MS Access, fwiw, Insert/update/delete queries are referred to as 'Action' queries. — Beth, Nov 20 '14 at 17:29
SQL is generally broken up into data manipulation, data definition, and data control statements. Data manipulation statements are SELECT, INSERT, etc. Data definition statements are ALTER, CREATE, etc. Data control statements are GRANT. — Gilbert Le Blanc, Nov 20 '14 at 18:02

score 1 · Accepted Answer · answered Aug 14 '14 at 20:13

Section 4.22.2 of the SQL92 standard classifies statements that handle data as "SQL-data statements", out of which the statements that change data are a subcategory, "SQL-data change statements". It does not, however, define a category for SQL-data statements that do not change any data.

score 1 · Answer 2 · answered Nov 20 '14 at 17:26

1

I believe the correct term for operations that don't change data is 'query'.

And I believe the correct term for operations that do change data is 'command', which may or may not be idempotent.

Further reading: Command-query separation on Wikipedia.

answered Nov 20 '14 at 17:26

Chris Schiffhauer

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Is There a Term for Database Operations That Don't Change Data?

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