odbc_api

Function shared_connection_into_cursor

Source 
pub fn shared_connection_into_cursor<'env>(
    connection: SharedConnection<'env>,
    query: &str,
    params: impl ParameterCollectionRef,
    query_timeout_sec: Option<usize>,
) -> Result<Option<CursorImpl<StatementConnection<SharedConnection<'env>>>>, Error>
Expand description

Similar to crate::Connection::into_cursor, yet it operates on an Arc<Mutex<Connection>>. Arc<Connection> can be used if you want shared ownership of connections. However, Arc<Connection> is not Send due to Connection not being Sync. So sometimes you may want to wrap your Connection into an Arc<Mutex<Connection>> to allow shared ownership of the connection across threads. This function allows you to create a cursor from such a shared which also holds a strong reference to it.

§Parameters

  • query: The text representation of the SQL statement. E.g. “SELECT * FROM my_table;”.

  • params: ? may be used as a placeholder in the statement text. You can use () to represent no parameters. See the crate::parameter module level documentation for more information on how to pass parameters.

  • query_timeout_sec: Use this to limit the time the query is allowed to take, before responding with data to the application. The driver may replace the number of seconds you provide with a minimum or maximum value.

    For the timeout to work the driver must support this feature. E.g. PostgreSQL, and Microsoft SQL Server do, but SQLite or MariaDB do not.

    You can specify 0, to deactivate the timeout, this is the default. So if you want no timeout, just leave it at None. Only reason to specify 0 is if for some reason your datasource does not have 0 as default.

    This corresponds to SQL_ATTR_QUERY_TIMEOUT in the ODBC C API.

    See: https://learn.microsoft.com/en-us/sql/odbc/reference/syntax/sqlsetstmtattr-function