OpenMS::Internal::SqliteHelper Namespace Reference

Enumerations
enum class	SqlState { SQL_ROW , SQL_DONE , SQL_ERROR }

Functions
template<typename T >
UInt64	clearSignBit (T)
template<>
UInt64	clearSignBit (UInt64 value)
	only allow UInt64 specialization More...
SqlState	nextRow (sqlite3_stmt *stmt, SqlState current=SqlState::SQL_ROW)
	retrieves the next row from a prepared statement More...
template<typename ValueType >
bool	extractValue (ValueType *, sqlite3_stmt *, int)
	Extracts a specific value from an SQL column. More...
template<>
bool	extractValue< double > (double *dst, sqlite3_stmt *stmt, int pos)
template<>
bool	extractValue< int > (int *dst, sqlite3_stmt *stmt, int pos)
template<>
bool	extractValue< Int64 > (Int64 *dst, sqlite3_stmt *stmt, int pos)
template<>
bool	extractValue< String > (String *dst, sqlite3_stmt *stmt, int pos)
template<>
bool	extractValue< std::string > (std::string *dst, sqlite3_stmt *stmt, int pos)
bool	extractValueIntStr (String *dst, sqlite3_stmt *stmt, int pos)
	Special case where an integer should be stored in a String field. More...
double	extractDouble (sqlite3_stmt *stmt, int pos)
float	extractFloat (sqlite3_stmt *stmt, int pos)
	convenience function; note: in SQL there is no float, just double. So this might be narrowing. More...
int	extractInt (sqlite3_stmt *stmt, int pos)
Int64	extractInt64 (sqlite3_stmt *stmt, int pos)
String	extractString (sqlite3_stmt *stmt, int pos)
char	extractChar (sqlite3_stmt *stmt, int pos)
bool	extractBool (sqlite3_stmt *stmt, int pos)

Enumeration Type Documentation

SqlState

enum SqlState

strong

Enumerator
SQL_ROW
SQL_DONE
SQL_ERROR	includes SQLITE_BUSY, SQLITE_ERROR, SQLITE_MISUSE

Function Documentation

clearSignBit() [1/2]

UInt64 OpenMS::Internal::SqliteHelper::clearSignBit

(

T

)

Sql only stores signed 64bit ints, so we remove the highest bit, because some/most of our sql-insert routines first convert to string, which might yield an uint64 which cannot be represented as int64, and sqlite would attempt to store it as double(!), which will loose precision

clearSignBit() [2/2]

UInt64 OpenMS::Internal::SqliteHelper::clearSignBit ( UInt64  value )

inline

only allow UInt64 specialization

extractValue()

bool OpenMS::Internal::SqliteHelper::extractValue	(	ValueType *	,
		sqlite3_stmt *	,
		int
	)

Extracts a specific value from an SQL column.

dst Destination (where to store the value) stmt Sqlite statement object pos Column position

For example, to extract a specific integer from column 5 of an SQL statement, one can use:

sqlite3_stmt* stmt; sqlite3* db; SqliteConnector::prepareStatement(db, &stmt, select_sql); sqlite3_step(stmt);

double target; while (sqlite3_column_type(stmt, 0) != SQLITE_NULL) { extractValue<double>(&target, stmt, 5); sqlite3_step( stmt ); } sqlite3_finalize(stmt);

extractValue< double >()

bool OpenMS::Internal::SqliteHelper::extractValue< double >	(	double *	dst,
		sqlite3_stmt *	stmt,
		int	pos
	)

extractValue< int >()

bool OpenMS::Internal::SqliteHelper::extractValue< int >	(	int *	dst,
		sqlite3_stmt *	stmt,
		int	pos
	)

extractValue< Int64 >()

bool OpenMS::Internal::SqliteHelper::extractValue< Int64 >	(	Int64 *	dst,
		sqlite3_stmt *	stmt,
		int	pos
	)

extractValue< std::string >()

bool OpenMS::Internal::SqliteHelper::extractValue< std::string >	(	std::string *	dst,
		sqlite3_stmt *	stmt,
		int	pos
	)

extractValue< String >()

bool OpenMS::Internal::SqliteHelper::extractValue< String >	(	String *	dst,
		sqlite3_stmt *	stmt,
		int	pos
	)

extractValueIntStr()

bool OpenMS::Internal::SqliteHelper::extractValueIntStr	(	String *	dst,
		sqlite3_stmt *	stmt,
		int	pos
	)

Special case where an integer should be stored in a String field.

nextRow()

SqlState OpenMS::Internal::SqliteHelper::nextRow	(	sqlite3_stmt *	stmt,
		SqlState	current = SqlState::SQL_ROW
	)

retrieves the next row from a prepared statement

If you receive 'SqlState::SQL_DONE', do NOT query nextRow() again, because you might enter an infinite loop! To avoid oversights, you can pass the old return value into the function again and get an Exception which will tell you that there is buggy code!

Parameters

stmt	Sqlite statement object
current	Return value of the previous call to this function.

Returns

one of SqlState::SQL_ROW or SqlState::SQL_DONE

Exceptions

Exception::SqlOperationFailed

if state would be SqlState::ERROR