It should be great to be able to start a transaction inside a transaction

[ecochard]

nothing to do with real postgres transactions
but logically it should be great to be able to imbricate transactions inside the code.

just add something like

transactionSql.begin = ( callback ) => {
    return callback( this );
}

this way, when I have a connection or a transaction started by sql.begin i can pass the objet to a method that don't know if it's a transaction