mysql,c , Loop through database table and compare user input
Loop through database table and compare user input
Question:
Tag: mysql,c
I am trying to loop through the rows in a MySql table and compare the data in a certain column to some user input using C. Currently my code looks like this:
MYSQL *cxn = mysql_init(NULL);
MYSQL_RES *result;
unsigned int num_fields;
unsigned int num_rows;
char *query_string;
MYSQL_ROW *row;
if (mysql_real_connect(cxn, <em>/*blah blah blah**/</em>) == NULL) {
printf("Please restart the service.");
}
result = mysql_store_result(cxn);
num_rows = mysql_num_rows(result);
num_fields = mysql_num_fields(result);
while (row = mysql_fetch_row(result)) {
for (i = 0; i < num_fields; i++) {
//Confusion occurring here
//if (field[i] @ currentRow == "User input")
// printf("Win");
}
}
Answer:
If you are only looking for fields that match the input, you'll want to search the database using the input string. In other words, write your query string so that it only gives you results that match the user input. This will be much faster than searching through every returned row for your user input.
SELECT * FROM table WHERE Cars=input
If you do need every row to be returned, then you would want your code to read something like this
while (row = mysql_fetch_row(result)) {
for (i = 0; i < num_fields; i++) {
//Confusion occurring here
//if (row[i] == "User input") You can't compare strings in C with ==
if(strcmp(row[i], user_input) == 0))
printf("Win");
}
}
If your user input is a string, however, you'll want to compare using strcmp.
if(strcmp(row[i], user_input) == 0))
Related:
c,char,segmentation-fault,user-input,scanf
I need to get in one single shot different inputs from one single line. In particular I need to get a single char and then, depending on which char value I just read, it can be a string and an int or a string, an int and another string and...
mysql,sql,sql-server,database,stored-procedures
So I am working with a database where I will be purging various tables that contain rows that are older than 30days. I have fairly limited knowledge of SQL and wanted to know if there was a certain way to select the row that will be purged and the rows...
php,mysql
I use this query but I don't know how will I order this by DoctorName? $q=mysqli_query($link,"Select * from doctor where status='". $stat ."'"); ...
c#,mysql
My problem is that I can't connect to my website remote MySQL server. I have read all answers in stackoverflow.com, but I can't find right answer. Here's my C# code: using System; using System.Collections.Generic; using System.Data; using System.Data.SqlClient; namespace ConsoleApplication3 { class Program { static void Main(string[] args) { SqlConnection...
php,mysql
The query is supposed to do the following: Obtain the question and associated answers based on the identification number of the question. (In this case the identification number is called account_id. Order them so that each question (and it's appropriate answers) are lined up in order. The query: SELECT *...
mysql,database,date,cognos
I'm having an issue with Cognos 10. I'm trying to calculate the number of days between to dates so I use the _days_between( date1, date2 ) function. _days_between ([Derniere Date Changement diaphragme] , [Premiere Date Changement diaphragme]) I'm quite sure the two Dates are Date objects ( I set them...
c#,mysql
Hello I found this code snippet for Adding Values to MySQL Commands in C# MySqlCommand command = connection.CreateCommand(); command.CommandText = "INSERT INTO tb_mitarbeiter (Vorname) VALUES (?name)"; command.Parameters.AddWithValue("?name", mitarbeiter); connection.Open(); command.ExecuteNonQuery(); Now I want to add data to more than one coloumn, but if i try it like this: command.Parameters.AddWithValue("?id", Projektid,...
php,mysql,arrays,variables,multidimensional-array
i've this code, i'm trying to explode my date e.g "04 June 2015" to have the day and the month in other 2 variables, but i have all in a method, with an array, is it possible, my code doesn't work, it writes "Array[0]" why? while ($i < $number) {...
mysql,ruby-on-rails,rdbms
I see add_index ~ unique: true statement in schema.rband think uniqueness is constraint for table, not for index.Using index is one of way realizing uniqueness, Programmer should not designate to the RDBMS "how" and index quicken searching but take costs inserting. In fact, is there another way to keep uniqueness...
php,mysql,mysqli
This question already has an answer here: Compile Error: Cannot use isset() on the result of an expression 2 answers Error - Cannot use isset() on the result of an expression (you can use "null !== expression" instead) I'm getting the error above the start of the if statement...
javascript,php,jquery,mysql
I need to create dynamic text fields with a button (which simply adds a new row of dynamic text fields). Then I need to INSERT the data in a in the database. I borrowed an example of what I need done from someone else's question, the problem is, it uses...
mysql,sql
I've the following table in my PHPMYADMIN The desired output is headline impressions clicks Buy A new Iphone ...
c,prng,shift-register
I am trying to understand how change the galois LFSR code to be able to specify the output bit number as a parameter for the function mentioned below. I mean I need to return not the last bit of LFSR as output bit, but any bit of the LFSR (...
c,openssl,cryptography,rsa
#include <string.h> #include <openssl/aes.h> #include <openssl/rand.h> #include <openssl/bio.h> #include <openssl/rsa.h> #include <openssl/evp.h> #include <openssl/pem.h> #define RSA_LEN 2048 #define RSA_FACTOR 65537 int genRSA2048(unsigned char **pub,unsigned int *pub_l,unsigned char **priv,unsigned int *priv_l){ RSA *pRSA = NULL; pRSA = RSA_generate_key(RSA_LEN,RSA_FACTOR,NULL,NULL); if (pRSA){ pub_l = malloc(sizeof(pub_l)); *pub_l = i2d_RSAPublicKey(pRSA,pub); priv_l = malloc(sizeof(priv_l));...
c,scope
The following code is for replacing multiple consecutive spaces into 1 space. Although I manage to do it, I am confused in the use of curly braces. This one is actually running fine: #include <stdio.h> #include <stdlib.h> int main() { int ch, lastch; lastch = 'a'; while((ch = getchar())!= EOF)...
php,mysql
I have already programmed a basic invoicing system using PHP/MySQL which has a table structure as follows; Invoice table; invoice_id, invoice_date, customer_id, etc Invoice line table; invoice_line_id, invoice_id, quantity, price, description, etc I need the system to automatically generate future invoices at set intervals (for example every 1 week or...
c,armcc,predefined-macro
Is there Predefined-Macros define about byte order in armcc. I am a novice on the armcc.and sorry for my English. In gcc these are macros: __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__ __ORDER_BIG_ENDIAN__ __ORDER_PDP_ENDIAN__ ... Now I have to use armcc, Is there same like these with armcc? Thank a lot. by the way,the armcc...
mysql
I've tried multiple ways, all of them resulting in incorrect rows returned, so far I've tried SELECT * FROM table WHERE id=1 AND timestamp >= NOW() - INTERVAL 1 HOUR ORDER BY timestamp DESC LIMIT 1 .... AND timestamp > DATE_SUB(NOW(), INTERVAL 1 HOUR) ORDER BY timestamp DESC LIMIT 1...
php,mysql
I have a table name tblnetworkstatus and I have 11 columns Id issue_name affected_server affected_service issue_type priority duration status start_date end_date description I am getting id in affected_server and affected_service which I am storing in my DB, now I have three situations Either both affected_server and affected_service has been selected...
php,html,mysql,table,data
2 Questions... Scenario: I would like to query my database table via a form and then display the results that occur(if there are results) and my current situation is that it does work but it clears the form completely and leaves my to an empty page with just the results...
php,mysql
In database I am storing date value unix timestamp value for e.g.'1434952110' using time() now I am trying to compare todays value with this value as below $jobpostdate = date("Y-m-d");//today's date passing in database to compare query $sql = "SELECT jsp_title, jsp_subtitle, jsp_desc, jsp_location, jsp_date "; $sql .= "FROM js_projects...
c,strcpy
I'm wondering what this syntax of strcpy() does in line 65 and 66: 24 #define SEQX "TTCATA" 25 #define SEQY "TGCTCGTA" 61 M = strlen(SEQX); 62 N = strlen(SEQY); 63 x = malloc(sizeof(char) * (M+2)); /* +2: leading blank, and trailing \0 */ 64 y = malloc(sizeof(char) * (N+2)); 65...
php,mysql
Concatenating two field names from different tables using INNER JOIN during UPDATE statement. I am trying to concatenate two field names in a mysql update statement. This is what I have so far, needless to say it isn't working, any suggestions would be much appreciated. UPDATE products INNER JOIN sub_categories...
mysql,sql
Basically i want to inner join 3 tables and the case is understood by the query itself as follows. Tables: A has 2 columns column 1 and column 2 B has 2 columns column 3 and column 4 C has 3 columns column 5,column 6 and column 7 Query: select...
php,mysql,mysqli,sql-injection,sql-insert
I am new to PHP and hope someone can help me with this. I would like to store two values (an email and a password) in a MySQL db using PHP. The input is passed to the PHP page via Ajax in jQuery (through an onclick event on a website)....
php,mysql,sql,mysqli
This is the query I'm using to count how many events are booked for each category of bookings. SELECT Categories.name, count(case when locations.name ='loc 1' then 1 end) as Location1, count(case when locations.name ='loc 2' then 1 end) as Location2, count(case when locations.name ='loc 3' then 1 end) as Location3,...
mysql,excel,vba,date
I have one table like this: SHORT TERM BORROWING 1/6/2009 94304 12/31/2010 177823 6/30/2011 84188 12/31/2011 232144 6/30/2012 94467 9/30/2012 91445 12/31/2012 128523 3/31/2013 83731 6/30/2013 78330 9/30/2013 70936 12/31/2013 104020 3/31/2014 62345 6/30/2014 62167 9/30/2014 63494 12/31/2014 104239 3/31/2015 69056 I have another column which lists each date from...
php,mysql,image
I have a MySQL table with a column "rounds" and each "rounds" has his own photos. Exemple round1 has photos from start=380 end=385. This means it has 6 photos and the name of the photos contains 380,381,382,383,384 or 385 inside. I use this PHP code to display the photos from...
python,mysql
I'm using this code to create a database with tables in Python: def CreateDatabase(): global DB_CNX global DB_NAME cursor = DB_CNX.cursor() cursor.execute("""CREATE DATABASE IF NOT EXISTS {} DEFAULT CHARACTER SET 'utf8'""".format(DB_NAME)) cursor.execute("""CREATE TABLE IF NOT EXISTS NAMES(NAME VARCHAR(50) PRIMARY KEY NOT NULL)""") DB_CNX.close() But even if I use the syntax...
mysql
I am trying to create a temporary column that gives each set of five results a number so that I can group by.. I am having a lot of trouble trying to work out how to do this. I don't want to take any criteria into account, I want the...
mysql,sql
I want to find all the dealers who haven't had an order in 2015 yet. I know this query doesn't work but I thought it might be helpful to understand what I want to do. In this example I want to get just "Bob" as a result. He is the...
mysql
I am using the query SELECT count(enq.`enquiryId`), Month(enq.`date`), Year(enq.`date`) FROM enquiry enq GROUP BY MONTH(enq.`date`) But I get all year records. I just want to get Current or any input year(At Runtime) records. Please help....
c,format,sscanf,c-strings
A well known function of the scanf() functions is that you can pass a format to scan input according to this format. For my case, I cannot seem to find a solution searching this and this documentation. I have a string (sInput) as the following: #something VAR1 this is a...
c,pointers,dynamic-memory-allocation,behavior,realloc
Note, this question is not asking if realloc() invalidates pointers within the original block, but if it invalidates all the other pointers. I'm new to C, and am a bit confused about the nature of realloc(), specifically if it moves any other memory. For example: void* ptr1 = malloc(2); void*...
c,if-statement,macros,logic
#define MACRO(num, str) {\ printf("%d", num);\ printf(" is");\ printf(" %s number", str);\ printf("\n");\ } int main(void) { int num; printf("Enter a number: "); scanf("%d", &num); if (num & 1) { MACRO(num, "Odd"); } else { MACRO(num, "Even"); } return 0; } Please explain the above code (if/else condition and how...
mysql,sql,select,sum
I want to select the sum of values of my_field. The unit of my_field is in seconds. I don't want to exceed 24 hours, so when it exceeds 24 hours, I want it to select 24*60*60 = 86400. SELECT IF(SUM(my_field) > 86400, 86400, SUM(my_field)) ... This solution doesn't seem to...
mysql
I am working on a rather tricky SQL for my level of knowledge. I have searched and searched for an answer but haven't came across anything. Hopefully someone can shed some light on this. How can you stop SQL from outputting group of rows if the limit set is not...
php,mysql,arrays,oracle
PHP CODE -: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Untitled Document</title> </head> <body> <?php $rows =0; $fp = fopen("leave1.csv","r"); if($fp){ while(!feof($fp)){ $content = fgets($fp); if($content) $rows++; } } fclose($fp); //echo $rows; $_SESSION['rows'] = $rows; ?>...
php,mysql,pdo
First of all I should say that I started to learn PDO and trying to rewrite some old mine codes. Here is one that I found on tutorial for a jquery/ajax/pdo/mysql comment system which is working. This is the mysql_* part which I'm trying to rewrite -> file submit.php which...
c,memory-management,out-of-memory,realloc
I'm trying to implement some math algorithms in C on Windows 7, and I need to repeatedly increase size of my array. Sometimes it fails because realloc can't allocate memory. But if I allocate a lot of memory at once in the beginning it works fine. Is it a problem...
mysql
I have found a very similar question with exact same title here: Mysql, Check field value change?, but it is not exactly what I need. DB: MySql, Table: tbl_geodata I have query: SELECT id,timestamp,ver_fw FROM tbl_geodata WHERE imei LIKE '353227026533507' Result is: --Full data +------+---------------------+--------+ | id | timestamp |...
java,mysql,hibernate,java-ee,struts2
I have a view in MySQL database CREATE VIEW CustInfo AS SELECT a.custName, a.custMobile, b.profession, b.companyName, b.annualIncome FROM customer a INNER JOIN cust_proffessional_info b ON a.cust_id=b.cust_id Is there any way that i can call this view using Struts2 or in Hibernate. I have tried to search it but could not...
mysql,sql
[Aim] We would like to find out how often an event "A" ocurred before time "X". More concretely, given the dataset below we want to find out the count of the prior purchases. [Context] DMBS: MySQL 5.6 We have following dataset: user | date 1 | 2015-06-01 17:00:00 2 |...
mysql,regex
I have an issue while I fetch data from database using regular expression. While I search for 'man' in tags it returns tags contains 'woman' too; because its substring. SELECT '#hellowomanclothing' REGEXP '^(.)*[^wo]man(.)*$'; # returns 0 correct, it contains 'woman' SELECT '#helloowmanclothing' REGEXP '^(.)*[^wo]man(.)*$'; # returns 0 incorrect, it can...
c,arrays,loops,malloc,fread
I'm trying to allocate an array 64 bytes in size and then loop over the array indexes to put a read a byte each from the inputfile. but when I don't malloc() the array indexes, the loop stays in index0 (so each time it loops it replaces the content in...
php,mysql,select,sql-injection,associative-array
I am trying to set up PHP queries for MySQL in a way to prevent SQL injection (standard website). I had a couple of INSERT queries where changing this worked well but on the following SELECT I keep getting an error since the update and it looks like the while...
php,mysql,symfony2,doctrine2
I have two entities Skin and Email. I want Email to be a part of the Skin entity, however I can't use the console to update schema automatically right now, and that is probably why I can't get the relationship to work. So I want to store all the Emails...
mysql,database,phpmyadmin
I want to create a backup of my database using the phpmyadmin export function. the database can't have any down time so I need to know if running a database export will take the database down? I've looked on-line but all I get is instructions on how to export. No...
mysql,sql,database
I have this mysql table structure: ------------------------------------ | item_id | meta_key | meta_value | ------------------------------------ 159 category Bungalow 159 location Lagos 159 price 45000 160 category Bungalow 160 location Abuja 160 price 53500 ... 350 category Bungalow 350 location Lagos 350 price 32000 What I'd like to do is select...
mysql,performance,explain
I'm creating a DB from scratch and I'm trying to create queries with performance in mind. For test purpose I filled my tables with test data. My query needs to join 3 tables: 2 with millions of rows and the third with hundred thousands rows. How can I know my...