Microsoft introduced the APPLY operator in SQL Server 2005. Similar to a JOIN, it allows correlation between two table expressions. The key difference between the JOIN and APPLY operators is when you have a table-valued expression on the right side and want to evaluate it for each row from the left table expression. Since they produce similar results, when do you choose an APPLY versus a JOIN?
2025-11-07
The Tabular Model Definition Language (TMDL) provides a simpler way of defining Power BI Semantic Models. Unlike the JSON-based Tabular Model Scripting Language (TMSL), TMDL uses a more accessible tab-based format for specifying DAX measures, relationships, and Power Query code.
2025-11-05
You’re building a new table or adding a column, and you wanna know which datatype to use: VARCHAR or NVARCHAR?
2025-11-03
There are numerous use cases for multi-file imports of CSV files into a SQL Server table:
2025-10-31
2025-10-29
Knowing the usage from all workloads is definitely better than focusing on only the primary or a single secondary. But what if I want to make more informed decisions, incorporating row counts, size, and index columns into this output?
2025-10-27
Simon Galbraith, co-founder of Redgate and one of the creators of Simple Talk, remembers Andrew Clarke
2025-10-24
I’ve seen the SQL EXISTS keyword in Microsoft SQL Server T-SQL code and don’t understand it well. What does it do? How do I use it? Are there best practices around SQL IF EXISTS?
2025-10-22
VIEWs are an undervalued and underused feature in SQL. They basically consist of a query that has been given a name, and a parameter list, so can be used like an inline macro. Technically, you’re supposed to think of it as a virtual table.
2025-10-20
Most SQL bulk insert and SQL Server openrowset tutorials skip file access issues that can stop imports cold. Both the bulk insert statement and openrowset function rely on the SQL Server service account to read a source file. The SQL Server service account must have read permission on the file or its folder. It is also convenient to have read & execute as well as list folder content permissions.
2025-10-17
By Vinay Thakur
Continuing from Day 3 where we covered LLM models open/closed and their parameters, Today...
By Steve Jones
One of the nice things about Flyway Desktop is that it helps you manage...
By HeyMo0sh
Microsoft Fabric (not to be confused with the more general term “fabric” in DevOps)...
I'm fairly certain I know the answer to this from digging into it yesterday,...
Hi Team, I am trying to refresh the Azure Synapse Dedicated pool from production...
hi everyone I am not sure how to write the query that will produce...
I have some data in a table:
CREATE TABLE #test_data
(
id INT PRIMARY KEY,
name VARCHAR(100),
birth_date DATE
);
-- Step 2: Insert rows
INSERT INTO #test_data
VALUES
(1, 'Olivia', '2025-01-05'),
(2, 'Emma', '2025-03-02'),
(3, 'Liam', '2025-11-15'),
(4, 'Noah', '2025-12-22');
If I run this query, how many rows are returned?
SELECT *
FROM OPENJSON(
(
SELECT t.* FROM #test_data AS t FOR JSON PATH
)
) t; See possible answers