Struct odbc_safe::Statement

pub struct Statement<'con, 'param, 'col, C = NoCursor, A = Unprepared> { /* fields omitted */ }

A Statement is most easily thought of as an SQL statement, such as SELECT * FROM Employee.

• The statement's state
• The current statement-level diagnostics
• The addresses of the application variables bound to the statement's parameters and result set columns
• The current settings of each statement attribute

See Statement Handles

Specific to the rust wrapper of an ODBC Statement is, that we do keep track of the lifetimes of the parent Connection, parameters as well as columns bound to the Statement. Since it is possible to unbind the parameters and columns we have to keep track of their lifetimes seperatly.

Methods

impl<'con, 'param, 'col, S, A> Statement<'con, 'param, 'col, S, A>

fn as_raw(&self) -> SQLHSTMT

Provides access to the raw ODBC Statement Handle

fn bind_input_parameter<'p, T: ?Sized>(
    self,
    parameter_number: SQLUSMALLINT,
    parameter_type: DataType,
    value: Option<&'p T>
) -> Return<Statement<'con, 'p, 'col, S, A>, Self> where
    T: CDataType,
    'param: 'p, 

Binds a parameter to a parameter marker in an SQL Statement

Result

This method will destroy the statement and create a new one which may not outlive the bound parameter. This is to ensure that the statement will not derefernce an invalid pointer during execution. Use reset_parameters to reset the bound parameters and increase the 'param lifetime back to 'static.

Arguments

• parameter_number - Index of the marker to bind to the parameter. Starting at 1
• parameter_type - SQL Type of the parameter
• value - Reference to bind to the marker

See SQLBindParameter Function

fn bind_col<'col_new, T: ?Sized>(
    self,
    column_number: SQLUSMALLINT,
    value: &'col_new mut T,
    indicator: &'col_new mut SQLLEN
) -> Return<Statement<'con, 'param, 'col_new, S, A>, Self> where
    T: CDataType,
    'col: 'col_new, 

Binds a buffer and an indicator to a column.

See SQLBindCol:

fn reset_parameters(self) -> Statement<'con, 'static, 'col, S, A>

Unbinds the parameters from the parameter markers

fn reset_columns(self) -> Statement<'con, 'param, 'static, S, A>

Unbinds column buffers from result set.

impl<'con, 'param, 'col, C, A> Statement<'con, 'param, 'col, C, A> where
    C: CursorState, 

fn num_result_cols(&self) -> Return<SQLSMALLINT>

Returns the number of columns of the result set

See SQLNumResultCols

fn fetch(
    self
) -> ReturnOption<Statement<'con, 'param, 'col, Positioned, A>, Statement<'con, 'param, 'col, NoCursor, A>>

Advances Cursor to next row

See SQLFetch See Fetching a Row of Data

fn close_cursor(
    self
) -> Return<Statement<'con, 'param, 'col, NoCursor>, Statement<'con, 'param, 'col, C, A>>

Closes the cursor. Cursors only need to be closed explicitly if the Statement handle is intended to be reused, but a result set is not consumed.

See SQLCloseCursor See Closing the Cursor

fn describe_col<T: ?Sized>(
    &mut self,
    column_number: SQLUSMALLINT,
    column_name: &mut T,
    column_name_indicator: &mut SQLSMALLINT,
    nullable: &mut Nullable
) -> Return<Option<DataType>> where
    T: OutputBuffer, 

Return information about result set column

See SQLDescribeCol Function

impl<'con, 'param, 'col> Statement<'con, 'param, 'col, NoCursor, Unprepared>

fn with_parent(parent: &'con Connection) -> Return<Self>

Allocates a new Statement

fn prepare<T: ?Sized>(
    self,
    statement_text: &T
) -> Return<Statement<'con, 'param, 'col, NoCursor, Prepared>, Statement<'con, 'param, 'col, NoCursor>> where
    T: SqlStr, 

Prepares a Statement for execution by creating an Access Plan.

See SQLPrepare Function See Prepare and Execute a Statement (ODBC)

fn exec_direct<T: ?Sized>(
    self,
    statement_text: &T
) -> ReturnOption<ResultSet<'con, 'param, 'col, Unprepared>, Statement<'con, 'param, 'col, NoCursor>> where
    T: SqlStr, 

Executes a preparable statement, using the current values of the parametr marker variables.

• See SQLExecDirect
• See Direct Execution

impl<'con, 'param, 'col> Statement<'con, 'param, 'col, NoCursor, Prepared>

fn describe_col<T: ?Sized>(
    &mut self,
    column_number: SQLUSMALLINT,
    column_name: &mut T,
    column_name_indicator: &mut SQLSMALLINT,
    nullable: &mut Nullable
) -> Return<Option<DataType>> where
    T: OutputBuffer, 

Return information about result set column

See SQLDescribeCol Function

fn execute(self) -> ReturnOption<ResultSet<'con, 'param, 'col, Prepared>, Self>

Executes a prepared statement, using the current values fo the parameter marker variables if any parameter markers exist in the statement.

See SQLExecute Function See Prepared Execution

impl<'con, 'param, 'col, A> Statement<'con, 'param, 'col, Positioned, A>

fn get_data<T: ?Sized>(
    &mut self,
    col_or_param_num: SQLUSMALLINT,
    target: &mut T
) -> ReturnOption<Indicator> where
    T: CDataType, 

Retrieves data for a single column or output parameter.

See SQLGetData

Trait Implementations

impl<'con, 'param, 'col, C: Debug, A: Debug> Debug for Statement<'con, 'param, 'col, C, A>

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<'con, 'param, 'col, C> Diagnostics for Statement<'con, 'param, 'col, C>

fn diagnostics(
    &self,
    rec_number: SQLSMALLINT,
    message_text: &mut [SQLCHAR]
) -> ReturnOption<DiagResult>

Returns the current values of multiple fields of a diagnostic record that contains error, warning, and status information.