homework-jianmu/docs/examples/c/demo.c

134 lines
3.8 KiB
C

/*
* Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
*
* This program is free software: you can use, redistribute, and/or modify
* it under the terms of the GNU Affero General Public License, version 3
* or later ("AGPL"), as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
// TAOS standard API example. The same syntax as MySQL, but only a subset
// to compile: gcc -o demo demo.c -ltaos
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "taos.h" // TAOS header file
static void queryDB(TAOS *taos, char *command) {
int i;
TAOS_RES *pSql = NULL;
int32_t code = -1;
for (i = 0; i < 5; i++) {
if (NULL != pSql) {
taos_free_result(pSql);
pSql = NULL;
}
pSql = taos_query(taos, command);
code = taos_errno(pSql);
if (0 == code) {
break;
}
}
if (code != 0) {
fprintf(stderr, "Failed to run %s, reason: %s\n", command, taos_errstr(pSql));
taos_free_result(pSql);
taos_close(taos);
exit(EXIT_FAILURE);
}
taos_free_result(pSql);
}
void Test(TAOS *taos, char *qstr, int i);
int main(int argc, char *argv[]) {
char qstr[1024];
// connect to server
if (argc < 2) {
printf("please input server-ip \n");
return 0;
}
TAOS *taos = taos_connect(argv[1], "root", "taosdata", NULL, 0);
if (taos == NULL) {
printf("failed to connect to server, reason:%s\n", taos_errstr(NULL));
exit(1);
}
for (int i = 0; i < 100; i++) {
Test(taos, qstr, i);
}
taos_close(taos);
taos_cleanup();
}
void Test(TAOS *taos, char *qstr, int index) {
printf("==================test at %d\n================================", index);
queryDB(taos, "drop database if exists demo");
queryDB(taos, "create database demo");
TAOS_RES *result;
queryDB(taos, "use demo");
queryDB(taos, "create table m1 (ts timestamp, ti tinyint, si smallint, i int, bi bigint, f float, d double, b binary(10))");
printf("success to create table\n");
int i = 0;
for (i = 0; i < 10; ++i) {
sprintf(qstr, "insert into m1 values (%" PRId64 ", %d, %d, %d, %d, %f, %lf, '%s')", (uint64_t)(1546300800000 + i * 1000), i, i, i, i*10000000, i*1.0, i*2.0, "hello");
printf("qstr: %s\n", qstr);
// note: how do you wanna do if taos_query returns non-NULL
// if (taos_query(taos, qstr)) {
// printf("insert row: %i, reason:%s\n", i, taos_errstr(taos));
// }
TAOS_RES *result1 = taos_query(taos, qstr);
if (result1 == NULL || taos_errno(result1) != 0) {
printf("failed to insert row, reason:%s\n", taos_errstr(result1));
taos_free_result(result1);
exit(1);
} else {
printf("insert row: %i\n", i);
}
taos_free_result(result1);
}
printf("success to insert rows, total %d rows\n", i);
// query the records
sprintf(qstr, "SELECT * FROM m1");
result = taos_query(taos, qstr);
if (result == NULL || taos_errno(result) != 0) {
printf("failed to select, reason:%s\n", taos_errstr(result));
taos_free_result(result);
exit(1);
}
TAOS_ROW row;
int rows = 0;
int num_fields = taos_field_count(result);
TAOS_FIELD *fields = taos_fetch_fields(result);
printf("num_fields = %d\n", num_fields);
printf("select * from table, result:\n");
// fetch the records row by row
while ((row = taos_fetch_row(result))) {
char temp[1024] = {0};
rows++;
taos_print_row(temp, row, fields, num_fields);
printf("%s\n", temp);
}
taos_free_result(result);
printf("====demo end====\n\n");
}