![]() In case the IF condition is not true, the statement after THEN is executed.Database() function retrieves the current schema from the MySQL server.The information if the column sale_person_designation is present in the table sale_details is retrieved from information_schema. IF checks whether the column sale_person_designation already exists in the table sale_details within the NOT EXISTS() function.The above script is creating a procedure named addColumnToTable.Procedure addColumnToTable is created and called successfully. NOT EXISTS( (SELECT * FROM information_schema.COLUMNS WHERE TABLE_SCHEMA=DATABASE()ĪND COLUMN_NAME='sale_person_designation' AND TABLE_NAME='sale_details') )ĪLTER TABLE sale_details ADD sale_person_designation varchar(255) DELIMITER $$ĭROP PROCEDURE IF EXISTS addColumnToTable $$ We will now try to add the column named sale_person_designation with VARCHAR datatype to the sale_details table only after checking if the column already exists or not. Error Code: 1364 Field doesn’t have a default valueĬurrently, the table has only four columns.MySQL Delete Duplicate Rows but keep one.Remove all line breaks from a String in PHP.Remove characters from String before a character in PHP.Remove a string after the last slash in PHP.Remove the BOM (Byte Order Mark) from a String in PHP.Remove a SubString from a String in PHP.SELECT * FROM customer_details įigure 3 shows that both the records have been inserted to table customer_details.Looking for Something Search for: Search Recent Posts The concept is the same as having a subquery within the NOT EXISTS clause with an additional UNION query to join both the INSERTS. SELECT customer_name FROM customer_details WHERE customer_name = 'Jenefir'Ģ row(s) affected Records: 2 Duplicates: 0 Warnings: 0 SELECT 'Jenefir' as customer_name, '28 Canada' as customer_address SELECT customer_name FROM customer_details WHERE customer_name = 'Suveer' SELECT 'Suveer' as customer_name, '28 Street North America' as customer_address ![]() INSERT INTO customer_details (customer_name, customer_address) Observe the below query for the solution. Let us take an example to add two rows for customers ‘Suveer’ and ‘Jenefir’ only if the records with names ‘Suveer’ and ‘Jenefir’ do not exist. What if we have more than one record to be inserted, and before every insert, we want to ensure that the record with the same column value does not exist. INSERT multiple record if NOT EXISTS in MySQL This time the record was not inserted as customer_name ‘Veronica’ already existed in the table customer_details. INSERT INTO customer_details (customer_name,customer_address)Ġ row(s) affected Records: 0 Duplicates: 0 Warnings: 0 Observe the below query and response message. Since the record exists in the table with customer_name=’ Veronica‘, let us again try and insert the record with the same customer_name. SELECT * FROM customer_details įigure 2 shows that the record has been inserted. Since there is a ‘ NOT‘ keyword before EXISTS keyword, the query will INSERT the row. If the row does not exist in the table, then FALSE will be returned. Here in the subquery with the NOT EXISTS clause, we are selecting the record from table customer_details. SELECT customer_name FROM customer_details WHERE customer_name = 'Veronica'ġ row(s) affected Records: 1 Duplicates: 0 Warnings: 0 SELECT * FROM (SELECT 'Veronica' AS customer_name, '552 NewYork USA' AS customer_address) AS temp ![]() INSERT INTO customer_details (customer_name,customer_address) ![]() Looking for Something Search for: Search Recent Posts
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