SQL using If Not Null on a Concatenation - Stack Overflow
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 - Counting null and non-null values in a single... - Stack Overflow
SELECT COUNT(*), 'null_tally' AS narrative FROM us WHERE a IS NULL UNION SELECT COUNT(*), 'not_null_tally' AS narrative FROM
sql - Union to handle NULL values - Stack Overflow
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.
MySQL 8.0 Reference Manual :: B.6.4.3 Problems with NULL Values
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 is null and = null - Stack Overflow
What is the difference between … and … and why does the latter not work?
SQL Инъекции | Page 4 | ANTICHAT - Security online community
...20NULL,version(),NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL
SET CONCAT_NULL_YIELDS_NULL (Transact-SQL)... | Microsoft Docs
Например, SELECT 'abc' + NULL дает в результате NULL.For example, SELECT 'abc' + NULL yields NULL.
SQL NULL Values - IS NULL and IS NOT NULL
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
Заметка про NULL / Хабр
Существуют специальные операторы IS NULL и IS NOT NULL, которые позволяют производить сравнения с NULLами.
Modern SQL: NULL — purpose, comparisons, NULL in expressions...
Mapping to and from null. Null Propagates Through Expressions. Null in Aggregate Functions