![]() We hope this article helped you with insert or update related queries. We already have the row with customer_name = “Rasmus,” Hence, we get an action output message.Īction Output Message : 17:22:35 INSERT INTO customer_data (customer_id, customer_name, customer_place) SELECT * FROM (SELECT 6, “Rasmus”,”TestPlace”) AS tmp_name WHERE NOT EXISTS ( SELECT customer_name FROM customer_data WHERE customer_name = “Rasmus” ) LIMIT 1 0 row(s) affected Records: 0 Duplicates: 0 Warnings: 0 0.00047 sec.Ġ rows affected, so nothing new gets inserted. In MySQL, there is no INSERT INTO IF NOT EXISTS statement. In some relational databases, you can use the INSERT INTO IF NOT EXISTS, which tells the database engine only to insert the records if they exist in the target table. To have a better understanding of the concept, let us re-run the same query, this time. Instead of adding a duplicate record or throwing an exception, you can tell the database engine to take another action. Since we do not yet have a row with customer_id = 6 the query will insert a new row on running this query. SELECT customer_name FROM customer_data WHERE customer_name = "Rasmus" SELECT * FROM (SELECT 6, "Rasmus","TestPlace") AS tmp_name For whatever you know, it may be the table name that is wrong, making you accidentally insert invalid data in the wrong table. INSERT INTO customer_data (customer_id, customer_name, customer_place) If the field list mentions columns that don't exist, it may very well contain columns that accidentally match. Example: We want to add one more row to our table customer_data ( refer figure 1.1) or update based on customer_name. In this section, we will be using the NOT EXISTS keyword. MySQL Insert or Update conditional : NOT EXISTS Read more about REPLACE in the official documentation. ![]() ![]() Also, the action message output said 2 rows affected, which means one got deleted before inserting the other. It shows that customer_name and customer_place got changed in the row with customer_id=2. REPLACE INTO customer_data(customer_id, customer_name, customer_place) VALUES(2, "Hevika","Atlanta") Īction Output Message : 18:27:57 REPLACE INTO customer_data (customer_id, customer_name, customer_place) VALUES(2, “Hevika”,”Atlanta”) 2 row(s) affected 0.0023 secĭoing a select * again on customer_data gives the data as shown in figure 1.5. Observe the below query with an action output message received after running it. We will be using the same example from customer_data table. The difference is: If the new row to be inserted has the same value of the PRIMARY KEY or the UNIQUE index as the existing row, in that case, the old row gets deleted first before inserting the new one. Insert or Update into MySQL Table : using REPLACE INTO 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.As a result, the row will not be inserted into the table.Looking for Something Search for: Search Recent Posts If a row exists, the “ WHERE NOT EXISTS” clause will return a false value, and the “ SELECT” statement will not return any rows. When this clause is used with the subquery “ (SELECT * FROM =) ” checks if a row exists in the table that fulfills the condition. In MySQL, the “ WHERE NOT EXIST” clause prevents the insertion of rows if they already exist in the table when it is used in the “ INSERT INTO” statement with a subquery to define a condition. Insert a new Row Only if Data do not Exist Using the “WHERE NOT EXISTS” Clause You can notice nothing is changing in the table because the row already existed so MySQL has successfully ignored the insertion process without displaying the error: The output contains two tables displaying data of the table before and after executing the query. INSERT IGNORE INTO Customer (Id ,FirstName ,LastName ) VALUES ( 1, 'John', 'Doe' )
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