Microsoft SQL Server
- Getting started with Microsoft SQL Server
- Awesome Book
- Awesome Community
- Awesome Course
- Awesome Tutorial
- Awesome YouTube
- Advanced options
- Aggregate Functions
- Alias Names in Sql Server
- Analyzing a Query
- Backup and Restore Database
- Basic DDL Operations in MS SQL Server
- bcp (bulk copy program) Utility
- BULK Import
- CASE Statement
- CLUSTERED COLUMNSTORE
- COALESCE
- Common Language Runtime Integration
- Common Table Expressions
- Computed Columns
- Converting data types
- CREATE VIEW
- cross apply
- Cursors
- Data Types
- Database permissions
- Database Snapshots
- Dates
- DBCC
- DBMAIL
- Delimiting special characters and reserved words
- Drop Keyword
- Dynamic data masking
- Dynamic SQL
- Dynamic SQL Pivot
- Encryption
- Export data in txt file by using SQLCMD
- File Group
- Filestream
- FOR JSON
- FOR XML PATH
- Foreign Keys
- Full-Text Indexing
- Generating a range of dates
- GROUP BY
- IF...ELSE
- Index
- In-Memory OLTP (Hekaton)
- Insert
- INSERT INTO
- Installing SQL Server on Windows
- Isolation levels and locking
- Join
- JSON in Sql Server
- Last Inserted Identity
- Limit Result Set
- Logical Functions
- Managing Azure SQL Database
- MERGE
- Microsoft SQL Server Management Studio Shortcut Keys
- Migration
- Modify JSON text
- Move and copy data around tables
- Natively compiled modules (Hekaton)
- NULLs
- OPENJSON
- ORDER BY
- OVER Clause
- Pagination
- Parsename
- Partitioning
- Permissions and Security
- PHANTOM read
- PIVOT / UNPIVOT
- Primary Keys
- Privileges or Permissions
- Queries with JSON data
- Query Hints
- Query Store
- Querying results by page
- Ranking Functions
- Resource Governor
- Retrieve information about the database
- Retrieve Information about your Instance
- Row-level security
- Scheduled Task or Job
- Schemas
- SCOPE_IDENTITY()
- SELECT statement
- Sequences
- Service broker
- Sorting/ordering rows
- Spatial Data
- Split String function in Sql Server
- SQL Server Evolution through different versions (2000 - 2016)
- SQL Server Management Studio (SSMS)
- SQLCMD
- Stored Procedures
- Storing JSON in SQL tables
- String Aggregate functions in SQL Server
- String Functions
- Subqueries
- System database - TempDb
- Table Valued Parameters
- Temporal Tables
- The STUFF Function
- Transaction handling
- Transaction isolation levels
- Trigger
- TRY/CATCH
- UNION
- Use of TEMP Table
- User Defined Table Types
- Variables
- Declare a Table Variable
- Compound assignment operators
- Declare multiple variables at once, with initial values
- Updating a variable using SET
- Updating variables by selecting from a table
- Updating variables using SELECT
- Views
- WHILE loop
- Window functions
- With Ties Option
Microsoft SQL Server Variables Updating variables by selecting from a table
Example
Depending on the structure of your data, you can create variables that update dynamically.
DECLARE @CurrentID int = (SELECT TOP 1 ID FROM Table ORDER BY CreateDate desc)
DECLARE @Year int = 2014
DECLARE @CurrentID int = (SELECT ID FROM Table WHERE Year = @Year)
In most cases, you will want to ensure that your query returns only one value when using this method.
