Berkeley DB怎么在单个文件里创建多个表的例子

winston

来自：http://blog.vckbase.com/BastEt/archive/2009/08/18/38140.html

2. int main(int argc,char *argv[])
3. {
4. DB_ENV *dbenv;
5. int ret = db_env_create(&dbenv, 0);
6. dbenv->set_cachesize(dbenv, 0, 5 * 1024 * 1024, 0);
7. ret = dbenv->open(dbenv, "d:\\test\", DB_CREATE|DB_INIT_LOG| DB_INIT_MPOOL, 0);
9. {
10. DB *dbp1=NULL;
11. ret = db_create(&dbp1, dbenv, 0);
12. int flags = DB_CREATE;
13. ret = dbp1->open(dbp1, NULL, "kingstock.db", "test1", DB_BTREE, flags, 0);
14. dbp1->close(dbp1,0);
15. }
17. {
18. DB *dbp2=NULL;
19. ret = db_create(&dbp2, dbenv, 0);
20. int flags = DB_CREATE;
21. ret = dbp2->open(dbp2, NULL, "kingstock.db", "test2", DB_BTREE, flags, 0);
22. dbp2->close(dbp2,0);
23. }
25. dbenv->close(dbenv,0);
26. return 0;
27. }

复制代码

winston

1. #include <sys/types.h>
3. #include <errno.h>
4. #include <iostream>
5. #include <stddef.h>
6. #include <stdio.h>
7. #include <stdlib.h>
8. #include <string.h>
10. #pragma comment(lib,"libdb47.lib")
11. #include <db.h>
14. int main(int argc,char *argv[])
15. {
16. DB_ENV *dbenv;
17. int ret = db_env_create(&dbenv, 0);
18. dbenv->set_cachesize(dbenv, 0, 5 * 1024 * 1024, 0);
19. ret = dbenv->open(dbenv, "d:\\test\", DB_CREATE|DB_INIT_LOG| DB_INIT_MPOOL, 0);
21. {
22. DB *dbp1=NULL;
23. ret = db_create(&dbp1, dbenv, 0);
24. int flags = DB_CREATE;
25. ret = dbp1->open(dbp1, NULL, "kingstock.db", "test1", DB_BTREE, flags, 0);
27. for(int i=0;i<40960;i++)
28. {
29. DBT key, data;
30. memset(&key,0,sizeof(key));
31. memset(&data,0,sizeof(data));
32. key.data=&i;
33. key.size=4;
35. data.data=&i;
36. data.size=4;
38. dbp1->put(dbp1,NULL,&key,&data,NULL);
39. }
41. dbp1->close(dbp1,0);
42. }
44. {
45. DB *dbp2=NULL;
46. ret = db_create(&dbp2, dbenv, 0);
47. int flags = DB_CREATE;
48. ret = dbp2->open(dbp2, NULL, "kingstock.db", "test2", DB_BTREE, flags, 0);
50. for(int i=0;i<40960;i++)
51. {
52. DBT key, data;
53. memset(&key,0,sizeof(key));
54. memset(&data,0,sizeof(data));
55. key.data=&i;
56. key.size=4;
58. data.data=&i;
59. data.size=4;
61. dbp2->put(dbp2,NULL,&key,&data,NULL);
62. }
64. dbp2->close(dbp2,0);
65. }
67. dbenv->close(dbenv,0);
68. return 0;
69. }

复制代码

winston

下面是遍历，速度非常的快，我存几万条简单的记录基本上是瞬间完成

1. int main(int argc,char *argv[])
2. {
3. DB_ENV *dbenv;
4. int ret = db_env_create(&dbenv, 0);
5. dbenv->set_cachesize(dbenv, 0, 5 * 1024 * 1024, 0);
6. ret = dbenv->open(dbenv, "d:\\test\", DB_CREATE|DB_INIT_LOG| DB_INIT_MPOOL, 0);
8. {
9. DB *dbp1=NULL;
10. ret = db_create(&dbp1, dbenv, 0);
11. int flags = DB_CREATE;
12. ret = dbp1->open(dbp1, NULL, "kingstock.db", "test1", DB_BTREE, flags, 0);
14. DBC *cursorp;
15. DBT key, data;
16. dbp1->cursor(dbp1, NULL, &cursorp, 0);
17. memset(&key, 0, sizeof(DBT));
18. memset(&data, 0, sizeof(DBT));
19. while ((ret = cursorp->get(cursorp, &key, &data, DB_NEXT)) == 0)
20. {
21. int *pkey=(int *)key.data;
22. printf("Table 1:%d\n",*pkey);
23. }
24. cursorp->close(cursorp);
27. dbp1->close(dbp1,0);
28. }
30. {
31. DB *dbp2=NULL;
32. ret = db_create(&dbp2, dbenv, 0);
33. int flags = DB_CREATE;
34. ret = dbp2->open(dbp2, NULL, "kingstock.db", "test2", DB_BTREE, flags, 0);
36. DBC *cursorp;
37. DBT key, data;
38. dbp2->cursor(dbp2, NULL, &cursorp, 0);
39. memset(&key, 0, sizeof(DBT));
40. memset(&data, 0, sizeof(DBT));
41. while ((ret = cursorp->get(cursorp, &key, &data, DB_NEXT)) == 0)
42. {
43. int *pkey=(int *)key.data;
44. printf("Table 1:%d\n",*pkey);
45. }
46. cursorp->close(cursorp);
48. dbp2->close(dbp2,0);
49. }
51. dbenv->close(dbenv,0);
52. return 0;
53. }

复制代码

modern

我们公司数据库底层也是基于Berkeley DB，呵呵

thinke365

原帖由 modern 于 2009-8-19 13:02 发表
我们公司数据库底层也是基于Berkeley DB，呵呵

为什么不是用mysql?