Sql server® 2012 t-sql fundamentals

  

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C H A P T E R   8

Data Modification

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QL has a set of statements known as Data Manipulation Language (DML) that deals with, well, data 

manipulation. Some people think that DML involves only statements that modify data, but in fact it 

also involves data retrieval. DML includes the statements SELECT, INSERT, UPDATE, DELETE, TRUNCATE, 

and MERGE. Up to this point in the book, I’ve focused on the SELECT statement. This chapter focuses 

on data modification statements. In addition to covering standard aspects of data modification, in this 

chapter, I’ll also cover aspects specific to T-SQL.

To avoid changing data in your existing sample databases, for demonstration purposes, most of 

the examples in this chapter create, populate, and operate against tables in the TSQL2012 database 

that use the dbo schema.

Inserting Data

T-SQL provides several statements for inserting data into tables: INSERT VALUES, INSERT SELECT, 

INSERT EXEC, SELECT INTO, and BULK INSERT. I’ll first describe those statements, and then I’ll talk 

about tools for automatically generating keys, such as the identity column property and the se-

quence object.