Ecto can only execute 1 sql statement at a time
Ecto can only ever execute 1 sql statement at a time, by design. For performance concerns, every statement is wrapped in a prepared statement<br />*some "security" is a fringe benefit of prepare statements.
In regards to the performance concerns of the prepared statement, PostgreSQL will force re-analysis of the statement when the objects in the statement have undergone definitional changes (DDL), making its use in a migration useless.
An example of a migration if you need to perform multiple statements:
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