Insert null value mysql php
Normally, you add regular values to mySQL, from PHP like this: Show
When your values are empty/null ($val1=="" or $val1==NULL), and you want NULL to be added to SQL and not 0 or empty string, to the following:
Note that null must be added as "NULL" and not as "'NULL'" . The non-null values must be added as "'".$val1."'", etc. Hope this helps, I just had to use this for some hardware data loggers, some of them collecting temperature and radiation, others only radiation. For those without the temperature sensor I needed NULL and not 0, for obvious reasons ( 0 is an accepted temperature value also). How to Replace an Empty String With NULL in MySQL Insert Query?Learn how to replace an empty string with NULL in MySQL/MariaDB
In this aricle we are going to see how we can insert
We'll be using the following build schema to build our table: CREATE TABLE `user` ( id INT NOT NULL AUTO_INCREMENT, name VARCHAR(25) NOT NULL, job_title VARCHAR(25), PRIMARY KEY (id) ); Using the NULLIF() Function The # Return NULL if expr1 = expr2 NULLIF(expr1, expr2) For example to insert INSERT INTO `user` (`name`, `job_title`) VALUES ('john', NULLIF('$jobTitle', '')); This would insert Using the IF() Function The IF(condition, expr1, expr2) We can simply have a condition to check if the value coming from a variable (e.g. " INSERT INTO `user` (`name`, `job_title`) VALUES ('john', IF('$jobTitle' = '', NULL, '$jobTitle')); Using the CASE Operator Using CASE WHEN condition1 THEN result1 # ... WHEN conditionN THEN resultN ELSE result END; The following example shows how, using INSERT INTO `user` (`name`, `job_title`) VALUES ( 'john', ( CASE WHEN '$jobTitle' = '' THEN NULL ELSE '$jobTitle' END ) ); Hope you found this post useful. It was published 04 Sep, 2020. Please show your love and support by sharing this post.
Inserting NULL valuesThe SQL INSERT statement can also be used to insert NULL value for a column. Example: Sample table: agents To add values'A001','Jodi','London','.12','NULL' for a single row into the table 'agents' then, the following SQL statement can be used: SQL Code:
SQL insert values in specific columnsThe SQL INSERT INTO statement can also be used to insert one or more specific columns for a row. It is required to mention the column(s) name in the SQL query. Example: Sample table: agents To add values'A001','Jodi', and ', 12' against the columns 'agent_code', 'agent_name' and 'commission' into the table 'agents', the following SQL statement can be used: SQL Code:
See our Model Database Here is a new document which is a collection of questions with short and simple answers, useful for learning SQL as well as for interviews. Practice SQL Exercises
Want to improve the above article? Contribute your Notes/Comments/Examples through Disqus. Previous: Insert
statement SQL: Tips of the DaySelect random rows: SELECT * FROM ( SELECT DISTINCT 1 + trunc(random() * 5100000)::integer AS id FROM generate_series(1, 1100) g ) r JOIN big USING (id) LIMIT 1000; Database: PostgreSQL Ref: https://bit.ly/3SwH0rN How do you insert a NULL value in MySQL?You can insert NULL value into an int column with a condition i.e. the column must not have NOT NULL constraints. The syntax is as follows. INSERT INTO yourTableName(yourColumnName) values(NULL);
How do you add NULL values?You also can specify the NULL keyword in the VALUES clause to indicate that a column should be assigned a NULL value. The following example inserts values into three columns of the orders table: INSERT INTO orders (orders_num, order_date, customer_num) VALUES (0, NULL, 123);
How do I insert a NULL value in a NOT NULL column?Code Inspection: Insert NULL into NOT NULL column
You cannot insert NULL values in col1 and col2 because they are defined as NOT NULL. If you run the script as is, you will receive an error. To fix this code, replace NULL in the VALUES part with some values (for example, 42 and 'bird' ).
How do I add NULL values in MySQL workbench?You can right-click on a cell and choose "Clear Field Content" in the popup menu. It will set the cell value to NULL.
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