W3Schools
w3schools.com › sql › sql_null_values.asp
SQL NULL Values - IS NULL and IS NOT NULL
SQL Examples SQL Editor SQL Quiz SQL Exercises SQL Server SQL Syllabus SQL Study Plan SQL Bootcamp SQL Certificate SQL Training ... A field with a NULL value is a field with no value.
GeeksforGeeks
geeksforgeeks.org › sql › sql-null-values
NULL values in SQL - GeeksforGeeks
July 23, 2025 - In SQL, some records in a table may not have values for every field, and such fields are termed as NULL values. These occur when data is unavailable during entry or when the attribute does not apply to a specific record.
query - Not equal to operator is not returning NULL values in SQL Server - Database Administrators Stack Exchange
I have the following query where I'm looking for any rows that are not equal to 1 for the column istrue. However, the results only include records with 0 and omit those with null. While I am aware ... More on dba.stackexchange.com
DBeaver: select from ODBC shows NULL where there are actual values
There is a fix for this, first go to the "ODBC DataSources" application. Select the DSN in question and click configure. At the bottom click the "data type options" that would open a window called "data type configuration". In the data type configuration window uncheck the options "use unicode" and "show boolean column as text". Then save the changes. Now delete the existing connection in DBeaver and create a new one for the ODBC source. You should not see NULL's anymore. (Please delete existing connection and create a new one, refreshing the connection does not work). More on reddit.com
6
2
April 25, 2022SELECT ... INTO OUTFILE export NULL as ""?
you can select ifnull(my_column, "") to turn it into "" at the select. More on reddit.com
3
1
December 15, 2015NetSuite SQL in Saved Search - Display NULL if the value is the same as the previous row?
Yes there is a way to do this. You need to use the sum/* comment */ partition by approach in this Prolecto article for a running subtotal by InternalID. https://blog.prolecto.com/2015/05/26/solving-the-netsuite-cumulative-saved-search-tally-challenge/ Then you need to know that there is a system variable called ROWNUM in Oracle (no curly braces because it's an Oracle system variable). So I'm pretty sure that ROWNUM resets to 1 each time that the partition window starts-over. Therefore, you can write a formula that only displays the subtotal amount when ROWNUM = 1. I don't have the exact formula anymore, but I did get this to work for a client, so I know it's possible. (It may have been Line Sequence Number in saved search instead of ROWNUM). Test it first with both ROWNUM and {linesequencenumber} and look how the row numbering works with both of these. Notice I changed the partition by to be internalID so it runs the sum for each InternalID. It would be something like this: case when ROWNUM = 1 then sum/* comment */({amount}) OVER(PARTITION BY {internalid} ORDER BY {internalid} ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW) else '' end More on reddit.com
3
5
May 22, 2020Videos
08:29
SQL to find NULL in any column - YouTube
11:40
How To Handle NULL Values In MS SQL Server? - YouTube
04:46
Understanding NULL Values in SQL | What NULL Means and How to Use ...
11:18
Working with SQL NULL values | Null Handling Functions - YouTube
00:42
Master NULL Values Fast: Explained in Under 1 Minutes! - YouTube
02:16
SQL - NULL Values - W3Schools.com - YouTube
DataLemur
datalemur.com › sql-tutorial › sql-null
Handling NULL Values | DataLemur
In SQL, indicates the absence of a value. Unlike an empty string or zero, doesn't represent a specific value, but rather, a missing or unknown piece of information. Here's an overview of what you'll learn in this tutorial: ... Handling NULL ...
Database Journal
databasejournal.com › home › features
Working with NULL Values in SQL | DatabaseJournal.com
March 9, 2023 - In relational databases and RDBMS’, NULL values are a special value in SQL that are used to represent an unknown – or in some instances, a missing – value in a column or cell.
special marker and keyword in SQL indicating that something has no value
Factsheet
Null (SQL)
Notation ω
Null (SQL)
Notation ω
Wikipedia
en.wikipedia.org › wiki › Null_(SQL)
Null (SQL) - Wikipedia
1 week ago - NULL is a special marker used to indicate that a data value does not exist in the database. Introduced by the creator of the relational database model, E. F. Codd, SQL null serves to fulfill the requirement that all true relational database ...
W3Schools
w3schools.com › sql › sql_ref_is_null.asp
SQL IS NULL
SQL Examples SQL Editor SQL Quiz SQL Exercises SQL Server SQL Syllabus SQL Study Plan SQL Bootcamp SQL Certificate SQL Training ... The IS NULL command is used to test for empty values (NULL values).
W3Schools
w3schools.com › sql › sql_isnull.asp
W3Schools.com
SQL Examples SQL Editor SQL Quiz SQL Exercises SQL Server SQL Syllabus SQL Study Plan SQL Bootcamp SQL Certificate SQL Training ... Suppose that the "UnitsOnOrder" column is optional, and may contain NULL values.
IBM
ibm.com › docs › en › db2-for-zos › 12.0.0
Application programming and SQL - Handling null values
A null value indicates the absence of a column value in a row. A null value is an unknown value; it is not the same as zero or all blanks.
Microsoft Learn
learn.microsoft.com › en-us › sql › t-sql › language-elements › null-and-unknown-transact-sql
NULL and UNKNOWN (Transact-SQL) - SQL Server | Microsoft Learn
A null value is different from an empty or zero value. No two null values are equal.
Medium
medium.com › @riat06 › behaviour-of-null-values-in-sql-48c18564c46
Behaviour of NULL values in SQL. How does null value affects different… | by Ria Thomas | Medium
August 30, 2024 - The thing to note about GROUP BY() here is that if the column being grouped on has null values, it considers NULL as a bucket to group. However, if it’s the other way around i.e if the GROUP BY() was on id and an aggregate function is used on the null values it will consider NULL as no value for that bucket.
Microsoft Learn
learn.microsoft.com › en-us › sql › connect › ado-net › sql › handle-null-values
Handling null values - ADO.NET Provider for SQL Server | Microsoft Learn
June 25, 2024 - A null value in a relational database is used when the value in a column is unknown or missing. A null is neither an empty string (for character or datetime data types) nor a zero value (for numeric data types).
SQL Shack
sqlshack.com › working-with-sql-null-values
Working with SQL NULL values
May 19, 2021 - If we widen this theoretical explanation, the NULL value points to an unknown value but this unknown value does not equivalent to a zero value or a field that contains spaces. Due to this structure of the NULL values, it is not possible to use traditional comparison (=, <, > and <>) operators in the queries. As a matter of fact, in the SQL Standards using the WHERE clause as the below will lead to return empty result sets.
GeeksforGeeks
geeksforgeeks.org › sql › sql-select-null
SQL - SELECT NULL - GeeksforGeeks
July 23, 2025 - A NULL value in SQL indicates that a field has no value. It is not equivalent to a zero or a blank space.
W3Schools
w3schools.com › mysql › mysql_null_values.asp
MySQL NULL Values - IS NULL and IS NOT NULL
The IS NULL operator is used to test for empty values (NULL values). The following SQL lists all customers with a NULL value in the "Address" field:
Tutorialspoint
tutorialspoint.com › sql › sql-null-values.htm
SQL - NULL Values
SQL uses the term NULL to represent a non-existent data value in the database. These values are not the same as an empty string or a zero. They don't hold any space in the database and are used to signify the absence of a value or the unknown value in a data field.
Oracle
docs.oracle.com › en › database › oracle › oracle-database › 26 › sqlrf › Nulls.html
SQL Language Reference
1 month ago - If a column in a row has no value, then the column is said to be null, or to contain null. Nulls can appear in columns of any data type that are not restricted by NOT NULL or PRIMARY KEY integrity constraints.
DB Vis
dbvis.com › thetable › the-definitive-guide-to-the-null-sql-server-value
The Definitive Guide to the NULL SQL Server Value
September 12, 2024 - In SQL Server, NULL indicates data that is unknown, not applicable, or yet to be provided. For example, assume a column for a middle name is nullable. In this case, NULL values indicate that the person either does not have a middle name or this ...
Top answer 1 of 6
19
Consider checking documentation:
NULL indicates that the value is unknown. A null value is different from an empty or zero value. No two null values are equal. Comparisons between two null values, or between a null value and any other value, return unknown because the value of each NULL is unknown.
2 of 6
7
If you consider that the value of istrue is unknown in the NULL case then it might or might not equal 1.
The expression istrue != 1 then evaluates to unknown
SQL only returns rows where the WHERE clause evaluates to true.
If you are on SQL Server 2022+ you can use
WHERE istrue IS DISTINCT FROM 1
To give the inequality semantics that you want (Fiddle).
Hightouch
hightouch.com › sql-dictionary › sql-is-null
SQL IS NULL - Syntax, Use Cases, and Examples | Hightouch
December 29, 2023 - A NULL value in a database represents the absence of data, and the IS NULL operator is used to identify and select rows that contain NULL values in a particular column. You would use the SQL IS NULL operator when you need to filter data from ...
DbSchema
dbschema.com › blog › tutorials › sql-null-values
SQL NULL Values Explained with Examples
August 22, 2023 - It is a distinct concept that represents missing or unknown data. In other words, NULL signifies the absence of any value. The IS NULL operator in SQL is used to check whether a column value is NULL or not.