Struct odbc_api::buffers::ColumnarRowSet

pub struct ColumnarRowSet { /* fields omitted */ }

A columnar buffer intended to be bound with crate::Cursor::bind_buffer in order to obtain results from a cursor.

This buffer is designed to be versatile. It supports a wide variaty of usage scenarios. It is efficient in retrieving data, but expensive to allocate, as columns are allocated seperatly. This is required in order to efficiently allow for rebinding columns, if this buffer is used to provide array input parameters those maximum size is not known in advance.

Most applications should find the overhead neglegible, especially if instances are reused.

Implementations

impl ColumnarRowSet

pub fn new(
    max_rows: u32,
    description: impl Iterator<Item = BufferDescription>
) -> Self

Allocates for each buffer description a buffer large enough to hold max_rows.

pub fn column(&self, column_index: usize) -> AnyColumnView<'_>

Use this method to gain access to the actual column data.

pub fn num_rows(&self) -> usize

Number of valid rows in the buffer.

Trait Implementations

impl RowSetBuffer for ColumnarRowSet

pub fn bind_type(&self) -> u32

Declares the bind type of the Row set buffer. 0 Means a columnar binding is used. Any non zero number is interpreted as the size of a single row in a row wise binding style.

pub fn row_array_size(&self) -> u32

The batch size for bulk cursors, if retrieving many rows at once.

pub fn mut_num_fetch_rows(&mut self) -> &mut usize

Mutable reference to the number of fetched rows.

pub unsafe fn bind_to_cursor(
    &mut self,
    cursor: &mut impl Cursor
) -> Result<(), Error>

Binds the buffer either column or row wise to the cursor.