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MySQL CONCAT returns NULL if any field contain NULL

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I have following data in my table "devices" … I executed below query … It returns result given below … How to come out of this so that it should ignore NULL AND result should be …

sql - CONCAT'ing NULL fields - Stack Overflow

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I have a table with three fields, FirstName, LastName and Email. Here's some dummy data: … Now, if I do: … Vitals for Joe is null, as there is a single null field. How do you overcome this behaviour?

postgresql - String concatenation with a null seems to... - Stack Overflow

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In Postgres: … I was expecting it would otherwise return 'test'. Is this desired behavior? Seems weird that string concatenation with a null value would nullify the entire string... Referring to pg docs …

mysql concate check not null - Stack Overflow

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I dont want to return null value, how to check not null or how to make isset cond in query …

MySQL :: MySQL 8.0 Reference Manual :: 12.5 String Functions

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CONCAT() returns NULL if any argument is NULL. Press CTRL+C to copy.

sql - Union to handle NULL values - Stack Overflow

stackoverflow.com

select a,b,null,null from table1 union select null,null,c,d from table2 union select null,null,null,null,e,f from table3.

SQL using If Not Null on a Concatenation - Stack Overflow

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If I have the table … This will display Firstname-Middlename-Surname e.g. … The second one (Jane’s) displays correct, however since John doesn’t have a middlename, I want it to ignore the second dash.

SQL Инъекции | Page 797 | ANTICHAT - Security online community

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...Null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,null,concat

MySQL 8.0 Reference Manual :: B.6.4.3 Problems with NULL Values

dev.mysql.com

mysql> SELECT NULL, 1+NULL, CONCAT('Invisible',NULL); To search for column values that are NULL, you cannot use an expr = NULL test. The following statement returns no rows, because expr = NULL is never true for any expression: Press CTRL+C to copy. mysql> SELECT * FROM my_table...

SQL NULL Values - IS NULL and IS NOT NULL

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The IS NOT NULL operator is used to test for non-empty values (NOT NULL values). The following SQL lists all customers with a value in the "Address" field: Example. SELECT CustomerName, ContactName, Address FROM Customers WHERE Address IS NOT NULL

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