![]() ![]() Output: Of the student table is displayed in the below output console:Ĭreate table contact (cont_id int, phone_number varchar(150)) Insert into student values (6,'saanvi','italy') Insert into student values(5,'kriti','america') Insert into student values(4,'ashish','india') Insert into student values(3,'rahul','london') Insert into student values(2,'aman','england') Insert into student values (1,'divya','france') create table student(stud_id int, stud_name varchar(150),city varchar(150)) Now we will create another two table student and contact to explain delete inner join:Ĭode #1: The two tables created are student and contact. It indicates that the deletion process has affected two rows. Output: of the above query in the output console: ![]() Insert into table2(id,quantity) values('t',105) ĭelete table1,table2 from table1 inner join table2 on table2.quantity=table1.id where table1.id=100 Insert into table2(id,quantity) values('s',104) Insert into table2(id,quantity) values('r',103) Insert into table2(id,quantity) values('q',102) Insert into table2(id,quantity) values('p',101) To explain delete inner join, we have created tables in the database named table1 and table2 and inserted five rows into them.Ĭode #1 – Creating table1 create table table1(id int primary key auto_increment) Ĭode #2 – Creating table2 create table table2(id varchar(100) primary key,quantity int not null) The examples mentioned are as follows: Example #1 Similarly, if we remove table2, the delete statement is only used to table1 and will only delete rows from table1. If we remove table1, the delete statement is only applied to table2 and will only delete rows from table2. Also, the condition followed by the where clause will result in rows in table1 and table2 that need to be deleted. In the above statement, table1.joining_col =table2.joining_col, the expression is the matching condition between table1 and table2 that needs to be deleted. For example, the following statement deletes records from table1 and table2 that satisfy a given condition: Delete table1,table2 from table1 INNER JOIN table2 on table1.joining_col=table2.joining_col where condition In MySQL, we use the inner join clause to delete rows or records that have matching values in the table. Require "config.Select col_name1,col_l_namen from table1 INNER JOIN table2 ON l_name=l_name $query is the string variable storing our SQL Here is sample code using Php PDO.Ĭonfig.php file is the database connection file. ( SELECT id FROM student_fee where student_fee.id=student.id) Executing delete query using PHP ScriptĪfter preparing the SQL we can execute the query from our PHP Script. ( SELECT * FROM student_fee where student_fee.id=student.id)ĭELETE FROM student WHERE student.id NOT IN ![]() LEFT JOIN student_fee on student_fee.id=student.idīy using NOT EXISTS and subquery DELETE FROM student WHERE NOT EXISTS Now we will remove such records from first table ( student ) for which matching record is not available in second table ( student_fee ).īy using left Join DELETE student FROM student This is required when we want to delete students who have not paid their fees. Three interlinked dropdown list Deleting records that don't exist in another table The SQL dump (dropdown3.sql) of these tables are available inside the zip file at the end of this page. These three tables are part of a script showing three interlinked dropdown list. INNER JOIN student_fee on student.id=student_fee.id and student.id=2 We know that there are two records in student_fee table and one record in student table for student id =2. We can delete linked records from two tables by using single query. This will delete records for which mark is less than 60. Here we are selectively deleting the records so we have to use WHERE clause to match the selection. Now let us delete records of the students who has got mark less than 60. We can delete records based on some selection. This is one way of deleting all the records from a table. This will remove all the records from the table. To delete all the records from the table we can use truncate command like this This query is used along with some condition to selectively delete records from the table. SQL to delete records using WHER condition and removing records from multiple tables by joiningĭelete query is used to delete records from the table.
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