Statement

Statements represent a query, and the different states that are involved during the use of said query.

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Constructors

Name	Description
Statement()	Creates an empty statement.
Statement(Database db, const char* query)	Prepares a query against the given database.

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Accessors

Name	Description
bool busy() const	Tells whether this statement has started to iterate.
bool ready() const	Tells whether this statement is ready to iterate (!busy).
bool empty() const	Checks whether this statement is empty.
int current_row_index() const	Returns the current row index (-1 if not busy).
Row& current_row() const	Returns the current row (empty if not busy).
int columns_number() const	Returns the number of columns in the result.
const std::string& column_name(int column) const	Returns the nth column name.
const std::vector<std::string>& columns_names() const	Returns all column names.
Database database() const	Returns the underlying database.
sqlite3_stmt* raw_data() const	Returns the underlying raw sqlite3_stmt*.

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Parameter binding

Name	Description
Proxy operator[](const ParameterKey& k)	Returns a Proxy to the parameter.
Proxy operator[](const ParameterName& n)	Returns a Proxy to the parameter.
Proxy operator[](const ParameterIndex& p)	Returns a Proxy to the parameter.
friend Statement& operator<<(Statement& s, const Parameter& p)	Binds the given parameter.
friend Statement& operator<<(Statement& s, const Parameters& ps)	Binds the given parameters.
Statement& bind(const Parameter& p)	Binds the given parameter.
Statement& bind(const Parameters& ps)	Binds the given parameters.
Statement& bind(const ParameterKey& k, const Value& v)	Binds the given parameter.
Statement& bind(const ParameterName& n, const Value& v)	Binds the given parameter.
Statement& bind(const ParameterIndex& i, const Value& v)	Binds the given parameter.

Notes

• Proxy are proxy objects that override the = operator, allowing you to write statement["pname"] = parameter;.

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Execution

Name	Description
Rows exec()	Execute a query -> rows
Rows exec(const Parameters& params)	Execute a query -> rows
void exec(const RowCallback& callback)	Execute a query, callback on each row
void exec(const RowCallback& callback, const Parameters& params)	Execute a query, callback on each row
RowRange result()	Execute a query -> row range.
RowRange result(const Parameters& params)	Execute a query -> row range.
bool step()	Steps once; returns false if end reached.
void reset()	Stops the current execution.

Notes:

• Rows store the whole query result in memory, while RowRange allows you to iterate on the results one database row at a time.
• Use the provided saw_foreach macro to iterate on a RowRange:

saw_foreach (const Row& r, db.result("select * from clients"))
{
  // do something with r
}

• Variants with a Parameters argument will perform parameter substitution.