Method 1: The method will display group wise duplicate leads. SELECT     eabhyasa_id, eabhyasa_name, eabhyasa_email, eabhyasa_mobile,stage_name,count(*) no_of_records FROM rns_leads as L     left join rns_stages as S on S.stg_id= E.eabhyasa_stg_id GROUP BY eabhyasa_email, eabhyasa_mobile HAVING count(*) > 1  Method 2: The below method will display all duplicate leads SELECT L.eabhyasa_id, L.eabhyasa_fname, L.eabhyasa_email, L.eabhyasa_mobile,S.stg_name, case when E.eabhyasa_cp_type=0 then "-" when E.eabhyasa_cp_type=1 then "Fssess" when E.eabhyasa_cp_type=2 then "full" when E.eabhyasa_cp_type=3 then "part1" when E.eabhyasa_cp_type=4 then "part2" when E.eabhyasa_cp_type=5 then "part3" when E.eabhyasa_cp_type=6 then "part4" end as Payment_Stage FROM rns_leads L left join gti_stages as S on S.stg_id= E.eabhyasa_stg_id INNER JOIN ( SELECT eabhyasa_email, eabhyasa_mobile,count(*) no_of_records FROM gt...

The below queries will remove all spaces, tabs characters, new line characters first and last space(s) from the table column. For replace all spaces :  UPDATE `table` SET `col_name` = REPLACE(`col_name`, ' ', '') For remove all tabs characters :  UPDATE `table` SET `col_name` = REPLACE(`col_name`, '\t', '' ) For remove all new line characters :  UPDATE `table` SET `col_name` = REPLACE(`col_name`, '\n', '') http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_replace For remove first and last space(s) of column :  UPDATE `table` SET `col_name` = TRIM(`col_name`) http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_trim

Some Common MySql Interview Questions and Answers For Experienced + Freshers Which mostly asked my interviewer during interview session, As you know MySql is highly popular relational database and good compatible with open source languages like PHP. Following list of basic Mysql question and answer surely help developers for getting new jobs. MySql Interview Questions and Answers Question: What is MySQL? MySQL is an open source relational database management system (RDBMS) that uses Structured Query Language, the most popular language for adding, accessing, and processing data in a database. Because it is open source, anyone can download MySQL and tailor it to their needs in accordance with the general public license. MySQL is noted mainly for its speed, reliability, and flexibility.   Question: Why MySQL is used? MySQL database server is reliable, fast and very easy to use. This software can be downloaded as freeware and can be downloaded from the internet   Ques...

How to Change a MySQL Database’s Table Prefix: A Step-by-Step Guide Introduction Changing the table prefix of a MySQL database is a common task for enhancing security or reorganizing database structures. This guide walks you through the process step by step, ensuring clarity and efficiency. Whether you're a developer or a site administrator, these instructions will help you tackle the task with confidence. Why Change Your Table Prefix? Enhanced Security : Default table prefixes, like wp_ in WordPress, are often targeted by attackers. Changing them can reduce vulnerabilities. Customization : A new prefix makes your database easier to identify in complex environments. Avoid Conflicts : Helps prevent issues when importing databases into shared environments. Changing a database table prefix is easy and here’s the simple step-by-step guide! For WordPress installations, it’s essential! How to change a prefix 1. In your text editor, change database_name, old_prefix_ and new_prefix_ to ...

Run this code at regular intervals, for example once per day: Code: DELETE FROM moviesdone WHERE datetimecol < NOW() - INTERVAL 7 DAY

Method 1: SELECT count(*) total,     SUM(case when trim(last_name) like 'a%' then 1 else 0 end) A,     SUM(case when trim(last_name) like 'b%' then 1 else 0 end) B,     SUM(case when trim(last_name) like 'c%' then 1 else 0 end) C,     SUM(case when trim(last_name) like 'd%' then 1 else 0 end) D,     SUM(case when trim(last_name) like 'e%' then 1 else 0 end) E,     SUM(case when trim(last_name) like 'f%' then 1 else 0 end) F,     SUM(case when trim(last_name) like 'g%' then 1 else 0 end) G,     SUM(case when trim(last_name) like 'h%' then 1 else 0 end) H,     SUM(case when trim(last_name) like 'i%' then 1 else 0 end) I,     SUM(case when trim(last_name) like 'j%' then 1 else 0 end) J,     SUM(case when trim(last_name) like 'k%' then 1 else 0 end) K,     SUM(case when trim(last_name) like 'l%' then 1 else 0 end) L,     SUM(case when trim(last...

First, use  NOT REGEXP  instead of  !=1 . To allow  +  at the start optionally, use  ^\\+? . Since  +  is a special character in regular expressions, it must be escaped with a backslash (which must be escaped with another backslash). You then need one or more digits ( [0-9]+ ), up to the end of the string  $ . $query="UPDATE table SET phone='NULL' WHERE phone NOT REGEXP '^\+?[0-9]+$'"; This will match anything that doesn't begin optionally with  + , followed by digits only. If you also need to permit hyphens and dots in the phone number, add them into the  []  character class: '^\\+?[0-9.-]+$'

SELECT * FROM table WHERE YEAR(date_created) = YEAR(CURRENT_DATE - INTERVAL 1 MONTH) AND MONTH(date_created) = MONTH(CURRENT_DATE - INTERVAL 1 MONTH)

That just means MySQL insists that you give the inner SELECT a name, like: SELECT MAX(counted) FROM (     SELECT COUNT(*) AS counted     FROM table_actions     WHERE status = "good"     GROUP BY user ) AS counts;

You can reset the counter with: ALTER TABLE tablename AUTO_INCREMENT = 1 For InnoDB you cannot set the auto_increment value lower or equal to the highest current index