Sqlite库的基本操作

Sqlite 基本操作

---

打开数据库

sqlite3* SQ_DB;
char *zErrMsg = 0;

int nRes =  sqlite3_open("test.db", &SQ_DB);
if (nRes!=SQLITE_OK)
{
	return -1;
}

执行sql语句

/* Create SQL statement */
std::string sql = "CREATE TABLE COMPANY("  
	"ID INT PRIMARY KEY NOT NULL," 
	"NAME   TEXTNOT NULL," 
	"AGEINT NOT NULL," 
	"ADDRESSCHAR(50)," 
	"SALARY REAL );";

/* Execute SQL statement */
nRes = sqlite3_exec(SQ_DB, sql.c_str(), 0, 0, 0);

if (nRes != SQLITE_OK){
	fprintf(stderr, "SQL error: %s
", zErrMsg);
	sqlite3_free(zErrMsg);
}
else{
	fprintf(stdout, "Table created successfully
");
}

查询结果

• 回调方式

    static int callback(void *NotUsed, int argc, char **argv, char **azColName)
    {
    	int i;
    	for (i = 0; i < argc; i++)
    	{
    		printf("%s = %s
  ", azColName[i], argv[i] ? argv[i] : "NULL");
    	}
    	printf("
  ");
    	return 0;
    }
  

• TABLE方式

    char **dbResult;
    int nRow = 0;
    int nColumn = 0;
    sql = "SELECT * FROM COMPANY";
    int result = sqlite3_get_table(SQ_DB, sql.c_str(), &dbResult, &nRow, &nColumn, 0);
  
    string strLine;
    for (int i=1; i<=nRow; i++)
    {
    	for (int j = 0; j<nColumn; j++)
    	{
    		strLine = dbResult[i*nColumn + j];
    		cout << setw(10) <<strLine;
    	}
    	cout<< endl;	
  
    }
    if (dbResult)
    {
    	sqlite3_free_table(dbResult);
    }
  

关闭数据库

sqlite3_close(SQ_DB);