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SQL Server - Tables

 What is Table?

              Tables are database objects that contain all the data in a database. In tables, data is logically organized in a row-and-column format similar to a spreadsheet. Each row represents a unique record, and each column represents a field in the record.

              There are different types of table available in SQL Server

1.       Partitioned Tables

2.       Temporal tables

3.       Wide Tables

4.       System Tables

Please refer the below link to more about the Tables.

https://learn.microsoft.com/en-us/sql/relational-databases/tables/tables?view=sql-server-ver16

 

Create a table in SQL Server

There are multiple ways to create a table in SQL server.

1.       Using Table designer SQL server Management Studio(SSMS)

2.       Using T SQL

 In this blog we are going to see about, creating table using the Transaction SQL.            

 Please find the generic basic syntax on create table using the SQL.

                            CREATE TABLE Table_Name(

 Column_Name1 DataType1,

 Colun_Name2 DataType2,

 Column_Name3 DataType3)

 

 CREATE and TABLE are the keywords used to create the table with proceeding with table name

After the table name we need to mention the column names to be stored in the table name.

We will create the sample table for storing the student details.  

              CREATE TABLE Student(

StudentRollNo INT,

StudentName VARCHAR(70),

Gender CHAR(1),

StudentDOB DATE

)

 Delete the table in SQL Server

              We can use the same way to delete the table in SQL server.

We can use the SSMS Object Explorer -> Right Click the Table and click the drop.

We can Use T SQL DROP command to delete the table

Syntax

                             DROP TABLE TableName

              We can use the below code to delete the table using the above command.

                             DROP TABLE Student    

              Notes : There are set of Limitations and restrictions apply while delete the table in SQL server. Please refer the below link on the same.

              https://learn.microsoft.com/en-us/sql/relational-databases/tables/delete-tables-database-engine?view=sql-server-ver16

 

Rename the Table in SQL Server

              We can use the same two way to rename the table in SQL server.

We can use the SSMS Object Explorer -> Right Click the Table and click the rename.

We can use pre defined Stored Procedure to rename the table name

Syntax

EXEC sp_rename ‘Table Name to be renamed along with Schema Name’, 'New table name';

              We can use the below code to rename the table using the below.

                             EXEC sp_rename 'dbo.Student', 'StudentDetils'

 

Notes : Please refer the below link for more info

              https://learn.microsoft.com/en-us/sql/relational-databases/tables/rename-tables-database-engine?view=sql-server-ver16

 

View the existing Table Definition

              We will often encounter the problem to view the table definition details while look into the existing SQL server DB. For that we can use the below.

1.       We can use the existing procedure sp_help to know about the table definition

Ex : EXEC sp_help 'dbo.student;

2.       Using the system tables we can view the table definition

SELECT s.name as schema_name, t.name as table_name, c.* FROM sys.columns AS c INNER JOIN sys.tables AS t ON t.object_id = c.object_id INNER JOIN sys.schemas AS s ON s.schema_id = t.schema_id WHERE t.name = 'mytable' AND s.name = 'dbo';

 

3.       Using the SSMS object explorer design option

Refer the below link to know more about this

              https://learn.microsoft.com/en-us/sql/relational-databases/tables/view-the-table-definition?view=sql-server-ver16

 

View the dependencies of the Table in SQL server

We will often encounter the problem to view the table dependency details while look into the existing SQL server DB for modification. For that we can use the below.

1.       We can use the existing view to search about dependency of all SQL Server Objects

USE AdventureWorks2012; 

GO 

SELECT * FROM sys.sql_expression_dependencies 

WHERE referencing_id = OBJECT_ID(N'Production.vProductAndDescription');  

GO 

2.       Using the SSMS object explorer design option right click the table and click on view dependencies to vie the details.

Refer the below link to know more about this

              https://learn.microsoft.com/en-us/sql/relational-databases/tables/view-the-dependencies-of-a-table?view=sql-server-ver16

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