How to do it…

1. Initialize a MYSQL object:

mysql_init(NULL);

2. Establish a connection to the MySQL server running at the specified host. Also, establish a connection to the ecommerce database:

mysql_real_connect(conn, server, user, password, database, 0, NULL, 0)

3. Enter the email address of the user whose details you want to search for:

printf("Enter email address to search: ");
scanf("%s", emailaddress);

4. Create an SQL SELECT statement that searches the row in the users table that matches the email address that was entered by the user:

strcpy(sqlquery,"SELECT * FROM users where email_address like \'");
strcat(sqlquery,emailaddress);
strcat(sqlquery,"\'");

5. Execute the SQL SELECT statement. Terminate the program if the SQL query does not execute or some error occurs:

if (mysql_query(conn, sqlquery) != 0)                                 
{                                                                                                                                fprintf(stderr, "No row found in the users table with this email     address\n");                                                             
    exit(1);                                                                                     }  

6. If the SQL query executes successfully then the row(s) that matches the specified email address are retrieved and assigned to a resultset:

resultset = mysql_use_result(conn);

7. Use a while loop to extract one row at a time from the resultset and assign it to the array row:

while ((row = mysql_fetch_row(resultset)) != NULL)

8. The information of the entire row is shown by displaying the subscripts row[0], row[1], and row[2], respectively:

printf("Email Address: %s \n", row[0]);
printf("Password: %s \n", row[1]);
printf("Address of delivery: %s \n", row[2]);

9. Memory that's allocated to the resultset is freed up:

mysql_free_result(resultset);

10. The opened connection handler is closed:

mysql_close(conn);

The searchuser.c program for searching in a specific row in a MySQL database table is shown in the following code:

#include <mysql/mysql.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

void main() {
    MYSQL *conn;
    MYSQL_RES *resultset;
    MYSQL_ROW row;
    char *server = "127.0.0.1";
    char *user = "root";
    char *password = "Bintu2018$";
    char *database = "ecommerce";
    char emailaddress[30], sqlquery[255];
    conn = mysql_init(NULL);
    if (!mysql_real_connect(conn, server, user, password, database, 0, 
    NULL, 0)) {
        fprintf(stderr, "%s\n", mysql_error(conn));
        exit(1);
    }
    printf("Enter email address to search: ");
    scanf("%s", emailaddress);
    strcpy(sqlquery,"SELECT * FROM users where email_address like \'");
    strcat(sqlquery,emailaddress);
    strcat(sqlquery,"\'");
    if (mysql_query(conn, sqlquery) != 0)                 
    {                  
        fprintf(stderr, "No row found in the users table with this 
    email address\n");                  
        exit(1);                                                                     
    }  
    printf("The details of the user with this email address are as 
    follows:\n");
    resultset = mysql_use_result(conn);
    while ((row = mysql_fetch_row(resultset)) != NULL)
    {
        printf("Email Address: %s \n", row[0]);
        printf("Password: %s \n", row[1]);
        printf("Address of delivery: %s \n", row[2]);
    }
    mysql_free_result(resultset);
    mysql_close(conn);
}

Now, let's go behind the scenes to understand the code better.