kudu::client::KuduScanBatch Class Reference

A batch of zero or more rows returned by a scan operation. More...

#include <scan_batch.h>

List of all members.

Public Types
typedef RowPtr	value_type
	A handy typedef for the RowPtr.
Public Member Functions
int	NumRows () const
KuduScanBatch::RowPtr	Row (int idx) const
const_iterator	begin () const
const_iterator	end () const
const KuduSchema *	projection_schema () const
	RowPtr ()
bool	IsNull (const Slice &col_name) const
bool	IsNull (int col_idx) const
const void *	cell (int col_idx) const
std::string	ToString () const
KuduScanBatch::RowPtr	operator* () const
const_iterator &	operator++ ()
const_iterator	operator++ (int)
bool	operator== (const const_iterator &other) const
bool	operator!= (const const_iterator &other) const
Getters for integral type columns by column name.
Parameters: [in]  col_name  The name of the target column. [out]  val  Placeholder for the result value. Returns: Operation result status. Return a bad Status if at least one of the following is true: The type does not match. The value is unset. The value is NULL.
Status	GetBool (const Slice &col_name, bool *val) const WARN_UNUSED_RESULT
Status	GetInt8 (const Slice &col_name, int8_t *val) const WARN_UNUSED_RESULT
Status	GetInt16 (const Slice &col_name, int16_t *val) const WARN_UNUSED_RESULT
Status	GetInt32 (const Slice &col_name, int32_t *val) const WARN_UNUSED_RESULT
Status	GetInt64 (const Slice &col_name, int64_t *val) const WARN_UNUSED_RESULT
Status	GetUnixTimeMicros (const Slice &col_name, int64_t *micros_since_utc_epoch) const WARN_UNUSED_RESULT
Status	GetFloat (const Slice &col_name, float *val) const WARN_UNUSED_RESULT
Status	GetDouble (const Slice &col_name, double *val) const WARN_UNUSED_RESULT
Getters for integral type columns by column index.
These methods are faster than their name-based counterparts since using indices avoids a hashmap lookup, so index-based getters should be preferred in performance-sensitive code. Parameters: [in]  col_index  The index of the column. [out]  val  Pointer to the placeholder to put the resulting value. Returns: Operation result status. Return a bad Status if at least one of the following is true: The type does not match. The value is unset. The value is NULL.
Status	GetBool (int col_idx, bool *val) const WARN_UNUSED_RESULT
Status	GetInt8 (int col_idx, int8_t *val) const WARN_UNUSED_RESULT
Status	GetInt16 (int col_idx, int16_t *val) const WARN_UNUSED_RESULT
Status	GetInt32 (int col_idx, int32_t *val) const WARN_UNUSED_RESULT
Status	GetInt64 (int col_idx, int64_t *val) const WARN_UNUSED_RESULT
Status	GetUnixTimeMicros (int col_idx, int64_t *micros_since_utc_epoch) const WARN_UNUSED_RESULT
Status	GetFloat (int col_idx, float *val) const WARN_UNUSED_RESULT
Status	GetDouble (int col_idx, double *val) const WARN_UNUSED_RESULT
Getters for string/binary column by column name.
Get the string/binary value for a column by its name. Parameters: [in]  col_name  Name of the column. [out]  val  Pointer to the placeholder to put the resulting value. Note that the method does not copy the value. Callers should copy the resulting Slice if necessary. Returns: Operation result status. Return a bad Status if at least one of the following is true: The type does not match. The value is unset. The value is NULL.
Status	GetString (const Slice &col_name, Slice *val) const WARN_UNUSED_RESULT
Status	GetBinary (const Slice &col_name, Slice *val) const WARN_UNUSED_RESULT
Getters for string/binary column by column index.
Get the string/binary value for a column by its index. These methods are faster than their name-based counterparts since using indices avoids a hashmap lookup, so index-based getters should be preferred in performance-sensitive code. Parameters: [in]  col_index  The index of the column. [out]  val  Pointer to the placeholder to put the resulting value. Note that the method does not copy the value. Callers should copy the resulting Slice if necessary. Returns: Operation result status. Return a bad Status if at least one of the following is true: The type does not match. The value is unset. The value is NULL.
Status	GetString (int col_idx, Slice *val) const WARN_UNUSED_RESULT
Status	GetBinary (int col_idx, Slice *val) const WARN_UNUSED_RESULT
Friends
class	KuduScanner
class	tools::ReplicaDumper
class	KuduScanBatch
struct	SliceKeysTestSetup
struct	IntKeysTestSetup

---

Detailed Description

A batch of zero or more rows returned by a scan operation.

Every call to KuduScanner::NextBatch() returns a batch of zero or more rows. You can iterate over the rows in the batch using:

range-foreach loop (C++11):

   for (KuduScanBatch::RowPtr row : batch) {
     ... row.GetInt(1, ...)
     ...
   }

regular for loop (C++03):

   for (KuduScanBatch::const_iterator it = batch.begin(), it != batch.end();
        ++i) {
     KuduScanBatch::RowPtr row(*it);
     ...
   }

or

   for (int i = 0, num_rows = batch.NumRows();
        i < num_rows;
        i++) {
     KuduScanBatch::RowPtr row = batch.Row(i);
     ...
   }

Note:

In the above example, NumRows() is only called once at the beginning of the loop to avoid extra calls to the non-inlined method.

---

Member Function Documentation

KuduScanBatch::const_iterator kudu::client::KuduScanBatch::begin

(

)

const [inline]

Returns:

Forward iterator to the start of the rows in the batch.

const void* kudu::client::KuduScanBatch::cell

(

int

col_idx

)

const

Get the column's row data.

Note:

Should be avoided unless absolutely necessary.

Parameters:

[in]

col_idx

The index of the column.

Returns:

Raw cell data for the specified index.

KuduScanBatch::const_iterator kudu::client::KuduScanBatch::end

(

)

const [inline]

Returns:

Forward iterator to the end of the rows in the batch.

bool kudu::client::KuduScanBatch::IsNull

(

int

col_idx

)

const

Parameters:

[in]

col_idx

Index of the column.

Returns:

true iff the specified column of the row has NULL value.

bool kudu::client::KuduScanBatch::IsNull

(

const Slice &

col_name

)

const

Parameters:

[in]

col_name

Name of the column.

Returns:

true iff the specified column of the row has NULL value.

int kudu::client::KuduScanBatch::NumRows

(

)

const

Returns:

The number of rows in this batch.

bool kudu::client::KuduScanBatch::operator!=

(

const const_iterator &

other

)

const [inline]

An operator to check whether two iterators are 'not equal'.

Parameters:

[in]

other

The iterator to compare with.

Returns:

true iff the other iterator points to a different row in the same batch, or to a row belonging to a different batch altogether.

KuduScanBatch::RowPtr kudu::client::KuduScanBatch::operator*

(

)

const [inline]

Returns:

The row in the batch the iterator is pointing at.

const_iterator kudu::client::KuduScanBatch::operator++

(

int

)

[inline]

Postfix increment operator: advances the iterator to the next position.

Returns:

A copy of the iterator pointing to the pre-increment position.

const_iterator& kudu::client::KuduScanBatch::operator++

(

)

[inline]

Prefix increment operator: advances the iterator to the next position.

Returns:

The reference to the iterator, pointing to the next position.

bool kudu::client::KuduScanBatch::operator==

(

const const_iterator &

other

)

const [inline]

An operator to check whether two iterators are 'equal'.

Parameters:

[in]

other

The iterator to compare with.

Returns:

true iff the other iterator points to the same row of the same batch.

const KuduSchema* kudu::client::KuduScanBatch::projection_schema

(

)

const

Returns:

The projection schema for this batch. All KuduScanBatch::RowPtr returned by this batch are guaranteed to have this schema.

KuduScanBatch::RowPtr kudu::client::KuduScanBatch::Row

(

int

idx

)

const

Get a row at the specified index.

Parameters:

[in]

idx

The index of the row to return.

Returns:

A reference to one of the rows in this batch. The returned object is only valid for as long as this KuduScanBatch object is valid.

kudu::client::KuduScanBatch::RowPtr

(

)

[inline]

Construct an invalid RowPtr. Before use, you must assign a properly-initialized value.

std::string kudu::client::KuduScanBatch::ToString

(

)

const

Returns:

String representation for this row.

---

The documentation for this class was generated from the following file:

• include/kudu/client/scan_batch.h