嵌入式第四十一天(数据库)

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七.

#include <stdio.h>
#include <sqlite3.h>int main(int argc, const char *argv[])
{sqlite3 *pdb;int ret = sqlite3_open("./stu.db", &pdb);if (ret != SQLITE_OK){fprintf(stderr, "sqlite3_open error : %s\n", sqlite3_errmsg(pdb));return -1;}char *psql = "create table if not exists class3(id INTEGER, name TEXT, score REAL);";ret = sqlite3_exec(pdb, psql, NULL, NULL, NULL);if (ret != SQLITE_OK){fprintf(stderr, "sqlite3_exec error : %s\n", sqlite3_errmsg(pdb));sqlite3_close(pdb);return -1;}char sql[128] = {"insert into class3 values(1, \"zhangsan\", 99);"};ret = sqlite3_exec(pdb, sql, NULL, NULL, NULL);if (ret != SQLITE_OK){fprintf(stderr, "sqlite3_exec error : %s\n", sqlite3_errmsg(pdb));sqlite3_close(pdb);return -1;}sqlite3_close(pdb);return 0;
}

#include <stdio.h>
#include <sqlite3.h>int flag = 0;int callback(void *arg, int column, char **values, char **name)
{
//	printf("column = %d\n", column);if (0 == flag){for (int i = 0; i < column; i++){printf("%s ", name[i]);}printf("\n");flag = 1;}for (int i = 0; i < column; i++){printf("%s ", values[i]);}printf("\n");return 0;
}int main(int argc, const char *argv[])
{sqlite3 *pdb;int ret = sqlite3_open("./stu.db", &pdb);if (ret != SQLITE_OK){fprintf(stderr, "sqlite3_open error : %s\n", sqlite3_errmsg(pdb));return -1;}char *psql = "select * from data;";ret = sqlite3_exec(pdb, psql, callback, NULL, NULL);if (ret != SQLITE_OK){fprintf(stderr, "sqlite3_exec error : %s\n", sqlite3_errmsg(pdb));sqlite3_close(pdb);return -1;	}sqlite3_close(pdb);return 0;
}