mirror of
https://github.com/cuberite/SQLiteCpp.git
synced 2025-08-08 03:36:06 -04:00
Fix Savepoint comments and file formatting
Improved Savepoint description, it was mostly copy-pasted from Transaction with missing bits of information Conform to the SQLiteCpp code style, mainly braces have to be located on their own line
This commit is contained in:
parent
343299a31d
commit
4a9cc0adce
@ -14,28 +14,31 @@
|
||||
|
||||
#include <SQLiteCpp/Exception.h>
|
||||
|
||||
namespace SQLite {
|
||||
namespace SQLite
|
||||
{
|
||||
|
||||
// Foward declaration
|
||||
// Forward declaration
|
||||
class Database;
|
||||
|
||||
/**
|
||||
* @brief RAII encapsulation of a SQLite Savepoint.
|
||||
*
|
||||
* A Savepoint is a way to group multiple SQL statements into an atomic
|
||||
* secure operation; either it succeeds, with all the changes committed to the
|
||||
* database file, or if it fails, all the changes are rolled back to the initial
|
||||
* state at the start of the savepoint.
|
||||
* SAVEPOINTs are a method of creating Transactions, similar to BEGIN and COMMIT,
|
||||
* except that the SAVEPOINT and RELEASE commands are named and may be nested..
|
||||
*
|
||||
* Resource Acquisition Is Initialization (RAII) means that the Savepoint
|
||||
* begins in the constructor and is rolled back in the destructor (unless committed before), so that there is
|
||||
* no need to worry about memory management or the validity of the underlying SQLite Connection.
|
||||
*
|
||||
* This method also offers big performances improvements compared to
|
||||
* individually executed statements.
|
||||
*
|
||||
* Caveats:
|
||||
*
|
||||
* 1) Calling COMMIT or commiting a parent transaction or RELEASE on a parent
|
||||
* 1) Calling COMMIT or committing a parent transaction or RELEASE on a parent
|
||||
* savepoint will cause this savepoint to be released.
|
||||
*
|
||||
* 2) Calling ROLLBACK or rolling back a parent savepoint will cause this
|
||||
* 2) Calling ROLLBACK TO or rolling back a parent savepoint will cause this
|
||||
* savepoint to be rolled back.
|
||||
*
|
||||
* 3) This savepoint is not saved to the database until this and all savepoints
|
||||
@ -43,20 +46,16 @@ class Database;
|
||||
*
|
||||
* See also: https://sqlite.org/lang_savepoint.html
|
||||
*
|
||||
* Thread-safety: a Transaction object shall not be shared by multiple threads,
|
||||
* because:
|
||||
*
|
||||
* 1) in the SQLite "Thread Safe" mode, "SQLite can be safely used by multiple
|
||||
* threads provided that no single database connection is used simultaneously in
|
||||
* two or more threads."
|
||||
*
|
||||
* 2) the SQLite "Serialized" mode is not supported by SQLiteC++, because of the
|
||||
* way it shares the underling SQLite precompiled statement in a custom shared
|
||||
* pointer (See the inner class "Statement::Ptr").
|
||||
* Thread-safety: a Savepoint object shall not be shared by multiple threads, because:
|
||||
* 1) in the SQLite "Thread Safe" mode, "SQLite can be safely used by multiple threads
|
||||
* provided that no single database connection is used simultaneously in two or more threads."
|
||||
* 2) the SQLite "Serialized" mode is not supported by SQLiteC++,
|
||||
* because of the way it shares the underling SQLite precompiled statement
|
||||
* in a custom shared pointer (See the inner class "Statement::Ptr").
|
||||
*/
|
||||
|
||||
class Savepoint {
|
||||
public:
|
||||
class Savepoint
|
||||
{
|
||||
public:
|
||||
/**
|
||||
* @brief Begins the SQLite savepoint
|
||||
*
|
||||
@ -73,7 +72,7 @@ class Savepoint {
|
||||
Savepoint& operator=(const Savepoint&) = delete;
|
||||
|
||||
/**
|
||||
* @brief Safely rollback the savepoint if it has not been commited.
|
||||
* @brief Safely rollback the savepoint if it has not been committed.
|
||||
*/
|
||||
~Savepoint();
|
||||
|
||||
@ -83,13 +82,14 @@ class Savepoint {
|
||||
void release();
|
||||
|
||||
/**
|
||||
* @brief Rollback the savepoint
|
||||
* @brief Rollback to the savepoint, but don't release it.
|
||||
*/
|
||||
void rollback();
|
||||
|
||||
private:
|
||||
Database& mDatabase; ///< Reference to the SQLite Database Connection
|
||||
std::string msName; ///< Name of the Savepoint
|
||||
bool mbReleased = false; ///< True when release has been called
|
||||
private:
|
||||
Database& mDatabase; ///< Reference to the SQLite Database Connection
|
||||
std::string msName; ///< Name of the Savepoint
|
||||
bool mbReleased = false; ///< True when release has been called
|
||||
};
|
||||
|
||||
} // namespace SQLite
|
||||
|
@ -16,11 +16,13 @@
|
||||
#include <SQLiteCpp/Savepoint.h>
|
||||
#include <SQLiteCpp/Statement.h>
|
||||
|
||||
namespace SQLite {
|
||||
namespace SQLite
|
||||
{
|
||||
|
||||
// Begins the SQLite savepoint
|
||||
Savepoint::Savepoint(Database& aDatabase, const std::string& aName)
|
||||
: mDatabase(aDatabase), msName(aName) {
|
||||
: mDatabase(aDatabase), msName(aName)
|
||||
{
|
||||
// workaround because you cannot bind to SAVEPOINT
|
||||
// escape name for use in query
|
||||
Statement stmt(mDatabase, "SELECT quote(?)");
|
||||
@ -32,33 +34,46 @@ Savepoint::Savepoint(Database& aDatabase, const std::string& aName)
|
||||
}
|
||||
|
||||
// Safely rollback the savepoint if it has not been committed.
|
||||
Savepoint::~Savepoint() {
|
||||
if (!mbReleased) {
|
||||
try {
|
||||
Savepoint::~Savepoint()
|
||||
{
|
||||
if (!mbReleased)
|
||||
{
|
||||
try
|
||||
{
|
||||
rollback();
|
||||
release();
|
||||
} catch (SQLite::Exception&) {
|
||||
// Never throw an exception in a destructor: error if already rolled
|
||||
// back or released, but no harm is caused by this.
|
||||
}
|
||||
catch (SQLite::Exception&)
|
||||
{
|
||||
// Never throw an exception in a destructor: error if already released,
|
||||
// but no harm is caused by this.
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Release the savepoint and commit
|
||||
void Savepoint::release() {
|
||||
if (!mbReleased) {
|
||||
void Savepoint::release()
|
||||
{
|
||||
if (!mbReleased)
|
||||
{
|
||||
mDatabase.exec(std::string("RELEASE SAVEPOINT ") + msName);
|
||||
mbReleased = true;
|
||||
} else {
|
||||
}
|
||||
else
|
||||
{
|
||||
throw SQLite::Exception("Savepoint already released.");
|
||||
}
|
||||
}
|
||||
|
||||
// Rollback the savepoint
|
||||
void Savepoint::rollback() {
|
||||
if (!mbReleased) {
|
||||
// Rollback to the savepoint, but don't release it
|
||||
void Savepoint::rollback()
|
||||
{
|
||||
if (!mbReleased)
|
||||
{
|
||||
mDatabase.exec(std::string("ROLLBACK TO SAVEPOINT ") + msName);
|
||||
} else {
|
||||
}
|
||||
else
|
||||
{
|
||||
throw SQLite::Exception("Savepoint already released.");
|
||||
}
|
||||
}
|
||||
|
Loading…
x
Reference in New Issue
Block a user