T-SQL object selection: CTAS vs stored procedure vs view vs function

Verdict: Use CTAS to create and load a new table in one statement. Use a stored procedure for parameterised, multi-step loads with inserts, updates and branching, invoked by name from a pipeline. A view stores a query; it holds no rows.

Criterion	CTAS	Stored procedure	View	Scalar function
What it does	Creates and populates a new table in one statement	Encapsulates parameterised multi-step logic	Stores a reusable SELECT definition	Returns a single computed value
Persists data	Yes, physical table	Via its DML	No, virtual	No
DML and branching	One-time load only	Yes, insert, update, conditional	No	No
Invoked from a pipeline	As a statement	By name with EXEC	Referenced in queries	Used in expressions
Choose when	Build or stage a summarised table from existing data	Scheduled multi-step incremental load	Consistent query definition without storing rows	Compute one value in a query

Rules

Use CREATE TABLE AS SELECT (CTAS) to create and populate a new table from existing data in one statement.
Use a stored procedure for encapsulated, parameterised, multi-step logic with inserts, updates and branching, invoked by name from a pipeline.
Save as table in the SQL query editor persists a result set via CTAS; Save as view creates a stored query definition instead.
Generate a DimDate range with a T-SQL script or CTAS, adding derived columns like fiscal year and day-of-week name.

Traps

ALTER TABLE modifies an existing table; it does not create a new one populated with data.
A view holds a query definition, not materialised rows; Save as view does not create a physical table.
A scalar function returns one value and a view allows a single SELECT; neither supports multi-step DML.