db2connection.h

适合于Unix/Linux下的一个持久数据库连接池

// Copyright (c) 2000-2001  David Muse
// See the file COPYING for more information

#ifndef DB2CCONNECTION_H
#define DB2CCONNECTION_H

#define FETCH_AT_ONCE		10
#define MAX_SELECT_LIST_SIZE	256
#define MAX_ITEM_BUFFER_SIZE	4096

#define NUM_CONNECT_STRING_VARS 5

#include <sqlrconnection.h>

#include <sqlcli1.h>

struct db2column {
	char		name[MAX_ITEM_BUFFER_SIZE];
	uint16_t	namelength;
	// SQLColAttribute requires that these are signed, 32 bit integers
	int32_t		type;
	int32_t		length;
	int32_t		precision;
	int32_t		scale;
	int32_t		nullable;
	uint16_t	primarykey;
	uint16_t	unique;
	uint16_t	partofkey;
	uint16_t	unsignednumber;
	uint16_t	zerofill;
	uint16_t	binary;
	uint16_t	autoincrement;
};

class db2connection;

class db2cursor : public sqlrcursor_svr {
	friend class db2connection;
	public:
			db2cursor(sqlrconnection_svr *conn);
			~db2cursor();
	private:
		bool		prepareQuery(const char *query,
						uint32_t length);
		bool		inputBindString(const char *variable, 
						uint16_t variablesize,
						const char *value, 
						uint16_t valuesize,
						int16_t *isnull);
		bool		inputBindInteger(const char *variable, 
						uint16_t variablesize,
						int64_t *value);
		bool		inputBindDouble(const char *variable, 
						uint16_t variablesize,
						double *value, 
						uint32_t precision,
						uint32_t scale);
		bool		outputBindString(const char *variable, 
						uint16_t variablesize,
						char *value, 
						uint16_t valuesize,
						int16_t *isnull);
		bool		outputBindInteger(const char *variable,
						uint16_t variablesize,
						int64_t *value,
						int16_t *isnull);
		bool		outputBindDouble(const char *variable,
						uint16_t variablesize,
						double *value,
						uint32_t *precision,
						uint32_t *scale,
						int16_t *isnull);
		bool		executeQuery(const char *query,
						uint32_t length,
						bool execute);
		const char	*errorMessage(bool *liveconnection);
		bool		knowsRowCount();
		uint64_t	rowCount();
		bool		knowsAffectedRows();
		uint64_t	affectedRows();
		uint32_t	colCount();
		const char * const * columnNames();
		uint16_t	columnTypeFormat();
		void		returnColumnInfo();
		bool		noRowsToReturn();
		bool		skipRow();
		bool		fetchRow();
		void		returnRow();

		SQLRETURN	erg;
		SQLHSTMT	stmt;
		SQLSMALLINT	ncols;
		SQLINTEGER 	affectedrows;
		char		field[MAX_SELECT_LIST_SIZE]
					[FETCH_AT_ONCE]
					[MAX_ITEM_BUFFER_SIZE];
		SQLINTEGER	indicator[MAX_SELECT_LIST_SIZE]
						[FETCH_AT_ONCE];
#if (DB2VERSION>7)
		SQLUSMALLINT	rowstat[FETCH_AT_ONCE];
#endif
		db2column	col[MAX_SELECT_LIST_SIZE];
		char		*columnnames[MAX_SELECT_LIST_SIZE];

		uint64_t	rowgroupindex;
		uint64_t	totalinrowgroup;
		uint64_t	totalrows;
		uint64_t	rownumber;

		stringbuffer	*errormsg;

		db2connection	*db2conn;
};

class db2connection : public sqlrconnection_svr {
	friend class db2cursor;
	private:
		uint16_t	getNumberOfConnectStringVars();
		void	handleConnectString();
		bool	logIn(bool printerrors);
		sqlrcursor_svr	*initCursor();
		void	deleteCursor(sqlrcursor_svr *curs);
		void	logOut();
		int16_t	nullBindValue();
		bool	bindValueIsNull(int16_t isnull);
		bool	autoCommitOn();
		bool	autoCommitOff();
		bool	commit();
		bool	rollback();
		const char	*pingQuery();
		const char	*identify();
		const char	*dbVersion();
		const char	*bindFormat();

		SQLHENV		env;
		SQLRETURN	erg;
		SQLHDBC		dbc;

		const char	*server;

		char		dbversion[512];
};

#endif