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

236 lines
6.1 KiB
C

// TAOS standard API example. The same syntax as MySQL, but only a subet
// to compile: gcc -o prepare prepare.c -ltaos
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "taos.h"
void taosMsleep(int mseconds);
int main(int argc, char *argv[])
{
TAOS *taos;
TAOS_RES *result;
int code;
TAOS_STMT *stmt;
// connect to server
if (argc < 2) {
printf("please input server ip \n");
return 0;
}
taos = taos_connect(argv[1], "root", "taosdata", NULL, 0);
if (taos == NULL) {
printf("failed to connect to db, reason:%s\n", taos_errstr(taos));
exit(1);
}
result = taos_query(taos, "drop database demo");
taos_free_result(result);
result = taos_query(taos, "create database demo");
code = taos_errno(result);
if (code != 0) {
printf("failed to create database, reason:%s\n", taos_errstr(result));
taos_free_result(result);
exit(1);
}
taos_free_result(result);
result = taos_query(taos, "use demo");
taos_free_result(result);
// create table
const char* sql = "create table m1 (ts timestamp, b bool, v1 tinyint, v2 smallint, v4 int, v8 bigint, f4 float, f8 double, bin binary(40), blob nchar(10), varbin varbinary(16))";
result = taos_query(taos, sql);
code = taos_errno(result);
if (code != 0) {
printf("failed to create table, reason:%s\n", taos_errstr(result));
taos_free_result(result);
exit(1);
}
taos_free_result(result);
// sleep for one second to make sure table is created on data node
// taosMsleep(1000);
// insert 10 records
struct {
int64_t ts;
int8_t b;
int8_t v1;
int16_t v2;
int32_t v4;
int64_t v8;
float f4;
double f8;
char bin[40];
char blob[80];
int8_t varbin[16];
} v = {0};
int32_t boolLen = sizeof(int8_t);
int32_t sintLen = sizeof(int16_t);
int32_t intLen = sizeof(int32_t);
int32_t bintLen = sizeof(int64_t);
int32_t floatLen = sizeof(float);
int32_t doubleLen = sizeof(double);
int32_t binLen = sizeof(v.bin);
int32_t ncharLen = 30;
stmt = taos_stmt_init(taos);
TAOS_MULTI_BIND params[11];
params[0].buffer_type = TSDB_DATA_TYPE_TIMESTAMP;
params[0].buffer_length = sizeof(v.ts);
params[0].buffer = &v.ts;
params[0].length = &bintLen;
params[0].is_null = NULL;
params[0].num = 1;
params[1].buffer_type = TSDB_DATA_TYPE_BOOL;
params[1].buffer_length = sizeof(v.b);
params[1].buffer = &v.b;
params[1].length = &boolLen;
params[1].is_null = NULL;
params[1].num = 1;
params[2].buffer_type = TSDB_DATA_TYPE_TINYINT;
params[2].buffer_length = sizeof(v.v1);
params[2].buffer = &v.v1;
params[2].length = &boolLen;
params[2].is_null = NULL;
params[2].num = 1;
params[3].buffer_type = TSDB_DATA_TYPE_SMALLINT;
params[3].buffer_length = sizeof(v.v2);
params[3].buffer = &v.v2;
params[3].length = &sintLen;
params[3].is_null = NULL;
params[3].num = 1;
params[4].buffer_type = TSDB_DATA_TYPE_INT;
params[4].buffer_length = sizeof(v.v4);
params[4].buffer = &v.v4;
params[4].length = &intLen;
params[4].is_null = NULL;
params[4].num = 1;
params[5].buffer_type = TSDB_DATA_TYPE_BIGINT;
params[5].buffer_length = sizeof(v.v8);
params[5].buffer = &v.v8;
params[5].length = &bintLen;
params[5].is_null = NULL;
params[5].num = 1;
params[6].buffer_type = TSDB_DATA_TYPE_FLOAT;
params[6].buffer_length = sizeof(v.f4);
params[6].buffer = &v.f4;
params[6].length = &floatLen;
params[6].is_null = NULL;
params[6].num = 1;
params[7].buffer_type = TSDB_DATA_TYPE_DOUBLE;
params[7].buffer_length = sizeof(v.f8);
params[7].buffer = &v.f8;
params[7].length = &doubleLen;
params[7].is_null = NULL;
params[7].num = 1;
params[8].buffer_type = TSDB_DATA_TYPE_BINARY;
params[8].buffer_length = sizeof(v.bin);
params[8].buffer = v.bin;
params[8].length = &binLen;
params[8].is_null = NULL;
params[8].num = 1;
strcpy(v.blob, "一二三四五六七八九十");
params[9].buffer_type = TSDB_DATA_TYPE_NCHAR;
params[9].buffer_length = sizeof(v.blob);
params[9].buffer = v.blob;
params[9].length = &ncharLen;
params[9].is_null = NULL;
params[9].num = 1;
int8_t tmp[16] = {'a', 0, 1, 13, '1'};
int32_t vbinLen = 5;
memcpy(v.varbin, tmp, sizeof(v.varbin));
params[10].buffer_type = TSDB_DATA_TYPE_VARBINARY;
params[10].buffer_length = sizeof(v.varbin);
params[10].buffer = v.varbin;
params[10].length = &vbinLen;
params[10].is_null = NULL;
params[10].num = 1;
char is_null = 1;
sql = "insert into m1 values(?,?,?,?,?,?,?,?,?,?,?)";
code = taos_stmt_prepare(stmt, sql, 0);
if (code != 0){
printf("failed to execute taos_stmt_prepare. code:0x%x\n", code);
}
v.ts = 1591060628000;
for (int i = 0; i < 10; ++i) {
v.ts += 1;
for (int j = 1; j < 11; ++j) {
params[j].is_null = ((i == j) ? &is_null : 0);
}
v.b = (int8_t)i % 2;
v.v1 = (int8_t)i;
v.v2 = (int16_t)(i * 2);
v.v4 = (int32_t)(i * 4);
v.v8 = (int64_t)(i * 8);
v.f4 = (float)(i * 40);
v.f8 = (double)(i * 80);
for (int j = 0; j < sizeof(v.bin); ++j) {
v.bin[j] = (char)(i + '0');
}
taos_stmt_bind_param(stmt, params);
taos_stmt_add_batch(stmt);
}
if (taos_stmt_execute(stmt) != 0) {
printf("failed to execute insert statement.\n");
exit(1);
}
taos_stmt_close(stmt);
// query the records
stmt = taos_stmt_init(taos);
taos_stmt_prepare(stmt, "SELECT * FROM m1 WHERE v1 > ? AND v2 < ?", 0);
v.v1 = 5;
v.v2 = 15;
taos_stmt_bind_param(stmt, params + 2);
if (taos_stmt_execute(stmt) != 0) {
printf("failed to execute select statement.\n");
exit(1);
}
result = taos_stmt_use_result(stmt);
TAOS_ROW row;
int rows = 0;
int num_fields = taos_num_fields(result);
TAOS_FIELD *fields = taos_fetch_fields(result);
// fetch the records row by row
while ((row = taos_fetch_row(result))) {
char temp[256] = {0};
rows++;
taos_print_row(temp, row, fields, num_fields);
printf("%s\n", temp);
}
if (rows == 2) {
printf("two rows are fetched as expectation\n");
} else {
printf("expect two rows, but %d rows are fetched\n", rows);
}
// taos_free_result(result);
taos_stmt_close(stmt);
return 0;
}