litesql::Backend Class Reference

An abstract base class for interfacing with relational databases. More...

#include <backend.hpp>

Classes
class	Cursor
	An abstract base class for cursors that iterate result sets returned by relational database. More...
class	Result

Public Member Functions
virtual	~Backend ()
	empty
virtual bool	supportsSequences () const
	return true if backend supports CREATE SEQUENCE - SQL-statements
virtual std::string	getSQLType (AT_field_type fieldType, const std::string &length="") const
virtual std::string	getCreateSequenceSQL (const std::string &name) const
virtual std::string	getSeqSQL (const std::string &sname) const
virtual std::string	getRowIDType () const
	backend may want to set an AUTO_INCREMENT-attribute for table's primary key field. More...
virtual std::string	getInsertID () const
	if backend supports this, new primary key of the last insert is returned
virtual void	begin () const
	begin SQL transaction, may or may not have an effect
virtual void	commit () const
	commit SQL transaction
virtual void	rollback () const
	rollback SQL transaction
virtual Result *	execute (const std::string &query) const =0
	executes SQL-query More...
virtual Cursor *	cursor (const std::string &query) const =0
	executes SQL-query More...
virtual std::string	groupInsert (const Record &tables, const Records &fields, const Records &values, const std::string &sequence) const
	executes multiple INSERT-statements and assigns same 'row id' for first field of every record More...

Static Public Member Functions
static std::unique_ptr< Backend >	getBackend (const std::string &type, const std::string &connInfo) noexcept(false)
	returns a backend according to Backendtype in type, parameters are specific to backend and are separated by semicolon. More...

Detailed Description

An abstract base class for interfacing with relational databases.

Member Function Documentation

cursor()

virtual Cursor* litesql::Backend::cursor ( const std::string &  query ) const

pure virtual

executes SQL-query

Parameters

query

SQL-query to execute

Returns

Cursor-object which can be used to iterate result set row by row without loading everything to memory

execute()

virtual Result* litesql::Backend::execute ( const std::string &  query ) const

pure virtual

executes SQL-query

Parameters

query

SQL-query to execute

Returns

Result-object which holds result set of query

Referenced by groupInsert().

getBackend()

unique_ptr< Backend > Backend::getBackend ( const std::string &  type, const std::string &  connInfo  )

staticnoexcept

returns a backend according to Backendtype in type, parameters are specific to backend and are separated by semicolon.

Parameters

type	type of the database backend (supported are : "mysql","postgresql","sqlite3","odbc"
connInfo	database connection specific parameters (parameters are separated by semicolon)

Exceptions

DatabaseError

if no backend is found

getRowIDType()

virtual std::string litesql::Backend::getRowIDType ( ) const

inlinevirtual

backend may want to set an AUTO_INCREMENT-attribute for table's primary key field.

this method is to deliver the details to database schema

groupInsert()

string Backend::groupInsert ( const Record &  tables, const Records &  fields, const Records &  values, const std::string &  sequence  ) const

virtual

executes multiple INSERT-statements and assigns same 'row id' for first field of every record

Parameters

tables	destination tables for insert operation
fields	record of field names per table
values	record of values per table
sequence	sequence where row id-numbers are pulled

Returns

new row id

References litesql::escapeSQL(), execute(), getInsertID(), litesql::join(), litesql::Backend::Result::records(), and supportsSequences().

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

• backend.hpp
• backend.cpp