SQL PHP HTML ASP JavaScript articles and free scripts to download
 

Checking for matching record in MySQL table

We can just check MySql table to verify whether a record exist or not. Here we are not interested in collecting the actual data from table. We are interested in getting a reply of TRUE or FALSE from our command. We will try for one line command using PHP.

We need such a query while working on a member signup script. Here when member enters a userid in the signup form we need to verify with our existing table to know if the userid is already used by some other member. Some time we will have different pages with access to different groups of members ( here the members have different level of access ). So when the member visit a page we will check with our table the member has required level of privilege or not.

This conditional checking is done by using if condition in PHP. Let us see the code for checking the userid exist inside a MySQL table or not.

if(mysql_num_rows(mysql_query("SELECT userid FROM plus_signup WHERE userid = '$userid'"))){
// Code inside if block if userid is already there
}


The above sql query will return TRUE or FALSE depending on the presence of userid in MySQL table.
Discuss this tutorial at forum

List of SQL Tutorials


Further readings
Getting formatted date value from date field in MySQL
Formatting date and time before adding to date field of MySQL
Automatically updating / inserting current date and time value in a DATETIME field
Collecting records between two date ranges from MySQL table fields
Getting date values from MYSQL table in readable format including time
Difference in days between two date fields
Getting the year part from date field
Getting the month part from date field
Getting the day part from date field
Records of last one month from today by using date field
Records of present week days by using dayofweek function
 
Scripts
PHP
JavaScript
HOME
SQL Tutorial List
SQL (Home)
SQL Commands
AVG
Alter Table
Between
Count
Copy Table
Create Table
Delete
Distinct
Group by
Having
Insert
Inner Join
IN
Left join
Limit
Like
MAX
MIN
Order By
OR AND
Rand
Replace
Rename Table
Select Query
Sum
Union
Update
Where
Subscribe
Submit your email address and receive article and product notifications. Your email is safe with us.