Read and Write mysql in C Language

Read and Write mysql in C Language
Create a database

CREATE DATABASE tiger;CREATE TABLE `test` (    `id` int(11) NOT NULL auto_increment,    PRIMARY KEY (`id`));ALTER TABLE `test`    ADD COLUMN `name` varchar(20);

C language read/write Database

/* ===================================================== ============================================================ Name: mysqltest. c Author: Version: Copyright: Your copyright notice Description: Hello World in C, ansi-style ========================================== ======================================================= * /# include
 
  
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MYSQL * g_conn; // mysql connection MYSQL_RES * g_res; // mysql record set MYSQL_ROW g_row; // string array, mysql record line # define MAX_BUF_SIZE 1024 // maximum number of buffer bytes const char * g_host_name = "127.0.0.1"; const char * g_user_name = "root"; const char * g_password = "123456 "; const char * g_db_name = "tiger"; const unsigned int g_db_port = 3306; void print_mysql_error (const char * msg) {// print the last error if (msg) printf ("% s: % s \ n", msg, mysql_error (g _ Conn); else puts (mysql_error (g_conn);} int executesql (const char * SQL) {/* query the database according the SQL */if (mysql_real_query (g_conn, SQL, strlen (SQL) // return-1 if the request fails; // return 0 if the request fails; // successful execution} int init_mysql () {// initialize the connection // init the database connection g_conn = mysql_init (NULL);/* connect the database */if (! Mysql_real_connect (g_conn, g_host_name, g_user_name, g_password, g_db_name, g_db_port, NULL, 0) // if return-1 fails; // whether the connection is available if (executesql ("set names utf8") // if return-1; return 0; // return successful} int main (void) {puts ("!!! Hello World !!! ");/* Prints !!! Hello World !!! */If (init_mysql (); print_mysql_error (NULL); char SQL [MAX_BUF_SIZE]; sprintf (SQL, "INSERT INTO 'test' ('name ') VALUES ('testname') "); if (executesql (SQL) print_mysql_error (NULL); if (executesql (" SELECT * FROM 'test '")) // There is no semicolon print_mysql_error (NULL) at the end of the sentence; g_res = mysql_store_result (g_conn); // transfer the result set from the server to the local machine, mysql_use_result directly uses the record set int iNum_rows = mysql_num_rows (g_res) on the server; // get the number of record rows int iNum_fields = mysql_num_fields (g_res ); // obtain the number of record columns printf ("% d records in total, each record % d field \ n", iNum_rows, iNum_fields); puts ("id \ tname \ n "); while (g_row = mysql_fetch_row (g_res) // print the result set printf ("% s \ t % s \ n", g_row [0], g_row [1]); // first, the second field mysql_free_result (g_res); // release the result set mysql_close (g_conn); // close the link return EXIT_SUCCESS ;}
    
   
  
 

Compile

Install mysql and specify the mysqlclient header file and library directory during compilation.

gcc -l mysqlclient -I /usr/local/mysql/include/ -L /usr/local/mysql/lib/ mysqltest.c

Run

You need to create a soft link/usr/lib/libmysqlclient. so.18->/usr/local/mysql/lib/libmysqlclient. so.18 in the/usr/lib/directory.

ln -s /usr/local/mysql/lib/libmysqlclient.so.18 /usr/lib/libmysqlclient.so.18