Issue description

The schema from connection options is not set as the current schema

Expected Behavior

I would expect any query that I run via a QueryRunner or directly using the data source to be run in the schema that is set in the data source options (unless, of course, a SET SCHEMA statement is executed).

Actual Behavior

All queries are executed in the user's default schema, regardless of the schema set in data source options.

Steps to reproduce

const connection = new DataSource({
    type: "sap",
    username: "MY_USER",
    schema: "MY_SCHEMA",
    ...
});

await connection.initialize();

console.log(await connection.query(`SELECT CURRENT_SCHEMA FROM SYS.DUMMY`); // returns MY_USER instead of MY_SCHEMA

My Environment

Additional Context

Since #10123 was merged, migrations and e.g. QueryRunner.createTable are no longer working when the schema is different than the user name.

Relevant Database Driver(s)

• aurora-mysql
• aurora-postgres
• better-sqlite3
• cockroachdb
• cordova
• expo
• mongodb
• mysql
• nativescript
• oracle
• postgres
• react-native
• sap
• spanner
• sqlite
• sqlite-abstract
• sqljs
• sqlserver

Are you willing to resolve this issue by submitting a Pull Request?

Yes, I have the time, and I know how to start.