Provides direct read/write access to a blob. More...

#include <HFSQtLi.h>

Public Member Functions
	Blob (bool readWrite=false, bool autoOpen=true)
	Constructor. More...

	Blob (Blob &source)

bool	close (QString *errorMsg=nullptr)
	Closes the blob if open. More...

bool	open (QString *errorMsg=nullptr)
	Opens the blob if closed. More...

bool	open (qint64 rowid, QString *errorMsg=nullptr)
	Open the blob to a particular row id. More...

bool	reopenFast (qint64 newId, QString *errorMsg=nullptr)
	Reopens the blob with a new id. More...

bool	isOpen ()
	Checks if the blob is currently open. More...

bool	isReadWrite ()
	Returns the read/write mode. More...

bool	autoOpen ()
	Returns the autoOpen mode. More...

qint64	size ()
	Get the size of the blob. More...

bool	read (void *data, qsizetype size, qsizetype offset=0)
	Reads data from the blob. More...

QByteArray	read (qsizetype size, qsizetype offset=0)
	Read data from the blob an returns a QByteArray with read data. More...

QByteArray	readAll ()
	Reads all the data in the blob. More...

bool	write (const void *data, qsizetype size, qsizetype offset)
	Writes data to the blob. More...

bool	write (const QByteArray &data, qsizetype offset=0)
	Writes data to the blob. More...

QString	database ()
	Returns current database name. More...

QString	table ()
	Returns current table name. More...

QString	column ()
	Returns current column name. More...

qint64	rowId ()
	Returns current row id. More...

Functions to set parameters
The functions here are used to set all parameters needed for succesfully opening a blob. Warning Calling any function in this group with values differents from the ones already set closes the Blob if autoOpen is not true or reopens it if it is false
bool	set (Db db, const char database, const char table, const char column, qint64 rowid)
	Sets several parameters at once. More...

bool	set (Db db, const char database, const char table, const char column)
	Sets several parameters at once. More...

bool	set (Db db, const char database, const char *table, qint64 rowid)
	Sets several parameters at once. More...

bool	setDatabase (const char *database)
	Sets the database name. If not set it will "main". More...

bool	setTable (const char *table)
	Sets the table name. More...

bool	setColumn (const char *column)
	Sets the column name. More...

bool	setRowId (qint64 rowId)
	Sets the row id. More...

bool	setReadWrite (bool readWrite)
	Sets the read/write mode. More...

bool	setDbPointer (Db *db)
	Sets the connection this blob refers to. More...

void	setAutoOpen (bool newAutoOpen)
	Sets the autoOpen mode. More...

Protected Attributes
QExplicitlySharedDataPointer< Helper::BlobData >	m_data

Detailed Description

Provides direct read/write access to a blob.

Blob has two options that influence its behaviour:

readWrite set if the blob should be open in read-only mode (false) or in read-write mode (true)
autoOpen If set to true (default behaviour) after any call to function that sets parameters if all parameters needed for opening the blob (database pointer, table, column and row id) are set the function will try to open/reopen the blob. Note that in this case the functions will return true only if the open was successfull.

There are three ways of setting blob parameters:

Directly using any function to set parameters calls
Reading the Blob with a column containing a blob sets database pointer, database, table and column to the one of the blob
Reading the Blob with a column containing an integer sets the rowid

Typical usage case will be like setting everything by hand:

Blob b; // Note that auto-open is enabled by default

b.set(m_db, nullptr, "TestTable", "blobColumn", 4); // "main" database selected by default

HFSQtLi::Blob::Blob

Blob(bool readWrite=false, bool autoOpen=true)

Constructor.

Definition: HFSQtLi.h:1542

or set all the parameters except the rowid by hand and then using a "SELECT" to retive it

Blob b; // Note that auto-open is enabled by default
b.set(m_db, nullptr, "TestTable", "blobColumn"); // "main" database selected by default
m_db->executeSingle("SELECT rowid FROM TestTable WHERE name="Foo", b)

or set all the parameters via a select:

Blob b; // Note that auto-open is enabled by default

m_db->executeSingle("SELECT blobColumn, rowid FROM TestTable WHERE name="Foo", b, b);

Constructor & Destructor Documentation

◆ Blob()

HFSQtLi::Blob::Blob	(	bool	readWrite = `false`,
		bool	autoOpen = `true`
	)

inline

Constructor.

Parameters

readWrite	Read/write mode. See isReadWrite()
autoOpen.	See autoOpen()

Member Function Documentation

◆ autoOpen()

bool HFSQtLi::Blob::autoOpen ( )

inline

Returns the autoOpen mode.

If true the blob will try to automatically open the blob when all of db pointer, tableName, columnName and rowid are set.

Returns: autoOpen status

◆ close()

bool HFSQtLi::Blob::close ( QString * errorMsg = nullptr )

inline

Closes the blob if open.

Parameters

errorMsg Optional pointer to a string that will receive the error message

Returns: true on success or if the blob was already closed

◆ column()

QString HFSQtLi::Blob::column ( )

inline

Returns current column name.

Returns: String with column name or empty string if unset

◆ database()

QString HFSQtLi::Blob::database ( )

inline

Returns current database name.

Returns: String with database name

◆ isOpen()

bool HFSQtLi::Blob::isOpen ( )

inline

Checks if the blob is currently open.

Returns: True if the blob is open, false otherwise

◆ isReadWrite()

bool HFSQtLi::Blob::isReadWrite ( )

inline

Returns the read/write mode.

If false the blob is in read-only mode and any write call will fail.

Returns: Read/write status

◆ open() [1/2]

bool HFSQtLi::Blob::open	(	qint64	rowid,
		QString *	errorMsg = `nullptr`
	)

inline

Open the blob to a particular row id.

If the blob is closed tries to open it with the given id, if it is already open tries to reopen it with the new id.

Parameters

errorMsg Optional pointer to a string that will receive the error message

Returns: true on success, false on failure

◆ open() [2/2]

bool HFSQtLi::Blob::open ( QString * errorMsg = nullptr )

inline

Opens the blob if closed.

Parameters

errorMsg Optional pointer to a string that will receive the error message

Returns: true on success or if the blob was already opened

◆ read() [1/2]

QByteArray HFSQtLi::Blob::read	(	qsizetype	size,
		qsizetype	offset = `0`
	)

inline

Read data from the blob an returns a QByteArray with read data.

Parameters

size	Size of the buffer to read
offset	Offset in blob to read

Returns: QByteArray filled with read data, or an empty one on error

◆ read() [2/2]

bool HFSQtLi::Blob::read	(	void *	data,
		qsizetype	size,
		qsizetype	offset = `0`
	)

inline

Reads data from the blob.

Parameters

data	Pointer to the buffer to read
size	Size of the buffer to read
offset	Offset in blob to read

Returns: True on success, false on error

◆ readAll()

QByteArray HFSQtLi::Blob::readAll ( )

inline

Reads all the data in the blob.

This call is equivalent to read(size(), 0);

Returns: QByteArray fill with the data from blob or an empty one on error

◆ reopenFast()

bool HFSQtLi::Blob::reopenFast	(	qint64	newId,
		QString *	errorMsg = `nullptr`
	)

inline

Reopens the blob with a new id.

This function must be called on an open blob or it will return an error

Parameters

errorMsg Optional pointer to a string that will receive the error message

Returns: true on success

◆ rowId()

qint64 HFSQtLi::Blob::rowId ( )

inline

Returns current row id.

Returns: Current row id. Result is undefined if no row-id was set.

◆ set() [1/3]

bool Blob::set	(	Db *	db,
		const char *	database,
		const char *	table,
		const char *	column
	)

Sets several parameters at once.

Parameters

db	Database pointer
database	Name of the database
table	Name of table
column	Name of column

Returns: True on success, false on error

◆ set() [2/3]

bool Blob::set	(	Db *	db,
		const char *	database,
		const char *	table,
		const char *	column,
		qint64	rowid
	)

Sets several parameters at once.

Parameters

db	Database pointer
database	Name of the database
table	Name of table
column	Name of column
rowid	Row id

Returns: True on success, false on error

◆ set() [3/3]

bool Blob::set	(	Db *	db,
		const char *	database,
		const char *	table,
		qint64	rowid
	)

Sets several parameters at once.

Parameters

db	Database pointer
database	Name of the database
table	Name of table
rowid	Row id

Returns: True on success, false on error

◆ setAutoOpen()

void HFSQtLi::Blob::setAutoOpen ( bool newAutoOpen )

inline

Sets the autoOpen mode.

Note that setting autoOpen to true will not try to open the blob until the next call to setXXX.

Parameters

newAutoOpen New value.

◆ setColumn()

bool HFSQtLi::Blob::setColumn ( const char * column )

inline

Sets the column name.

Parameters

table String pointing to column name or NULL to unset.

Returns: True on success, false on error

◆ setDatabase()

bool HFSQtLi::Blob::setDatabase ( const char * database )

inline

Sets the database name. If not set it will "main".

Parameters

database String pointing to database name or NULL to unset.

Returns: True on success, false on error

◆ setDbPointer()

bool HFSQtLi::Blob::setDbPointer ( Db * db )

inline

Sets the connection this blob refers to.

Parameters

db	Pointer to an open connection

Returns: True on success

◆ setReadWrite()

bool HFSQtLi::Blob::setReadWrite ( bool readWrite )

inline

Sets the read/write mode.

Parameters

readWrite New value.

Returns: True on success, false on error

◆ setRowId()

bool HFSQtLi::Blob::setRowId ( qint64 rowId )

inline

Sets the row id.

Parameters

rowid Integer of the row id.

Returns: True on success, false on error

◆ setTable()

bool HFSQtLi::Blob::setTable ( const char * table )

inline

Sets the table name.

Parameters

table String pointing to table name or NULL to unset.

Returns: True on success, false on error

◆ size()

qint64 HFSQtLi::Blob::size ( )

inline

Get the size of the blob.

Returns: Size of the blob on success, -1 on error or if the blob is closed

◆ table()

QString HFSQtLi::Blob::table ( )

inline

Returns current table name.

Returns: String with table name or empty string if unset

◆ write() [1/2]

bool HFSQtLi::Blob::write	(	const QByteArray &	data,
		qsizetype	offset = `0`
	)

inline

Writes data to the blob.

Parameters

data	Data to write
offset	Offset in the blob to write

Returns: True on success, false on error

◆ write() [2/2]

bool HFSQtLi::Blob::write	(	const void *	data,
		qsizetype	size,
		qsizetype	offset
	)

inline

Writes data to the blob.

Parameters

data	Pointer to the buffer to write
size	Size of the buffer to write
offset	Offset in the blob to write

Returns: True on success, false on error

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

HFSQtLi/HFSQtLi.h
HFSQtLi/HFSQtLi.cpp

Public Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ Blob()

Member Function Documentation

◆ autoOpen()

◆ close()

◆ column()

◆ database()

◆ isOpen()

◆ isReadWrite()

◆ open() [1/2]

◆ open() [2/2]

◆ read() [1/2]

◆ read() [2/2]

◆ readAll()

◆ reopenFast()

◆ rowId()

◆ set() [1/3]

◆ set() [2/3]

◆ set() [3/3]

◆ setAutoOpen()

◆ setColumn()

◆ setDatabase()

◆ setDbPointer()

◆ setReadWrite()

◆ setRowId()

◆ setTable()

◆ size()

◆ table()

◆ write() [1/2]

◆ write() [2/2]