SQL Server Database Connectivity issues

Unable to open the requested database in login ' Patdb '. Login failed.

User ' xp-201005191456\huting ' login failed.

Problems encountered and solutions

1.vs2010 Connect sqlserver2008 Prompt to open the requested database in the login ' Patdb '. Login failed. User ' xp-201005191456\huting ' login failed.

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VS2010 Server Explorer-data connection----ADD Link---Server name select xp-201005191456\sqlexpress---Windows Province authentication---Connect to a database---test connection, Show successful Connection---"OK, you can

2. Right-click on the connected database on the Server Explorer, point properties. See the connection string

Data source=xp-201005191456\sqlexpress;initial catalog=patdb;integrated Security=true

Copy the above connection string into the VS2010 connection string---string connstring= "Data source=xp-201005191456\sqlexpress;initial catalog=patdb;i ntegrated security=true ";

Prompt error

\SQLExpress, indicating an unrecognized escape sequence

Workaround: String [email protected] "Data source=xp-201005191456\sqlexpress;initial catalog=patdb;integrated security=true "

Connection Database Successful

3 in the SQL SERVER table, insert a new field

ALTER TABLE doc_exa ADD column_b VARCHAR () NULL

Doc_exa is the table name

Column_b is the newly added field

VARCHAR (20) is the type and length of the newly added field

ALTER TABLE pat_info ADD Pet class VARCHAR (+) NULL

SELECT * FROM Pat_info

4 The field order of the SQL Server 2008 data table is adjusted after you save the prompt error

Start SQL Server Management Studio

The Tools menu----options----Designers (designer)----prevent saving changes that require you to recreate the table uncheck the box.

5 SQL How to insert data

Insert Intopat_info (number, pet category, name, origin, age, fur color, price, place of trade, notes) VALUES (5, ' dog ', ' Tibetan mastiff ', ' Inner Mongolia ', 4, ' white ', 4000, ' Beijing ', ' Hero Dog ')

Insertinto Table name (Field 1, Field 2, Field 3) values (the value of field 1, the value of field 2, the value of field 3);

SQL Server 2008 also extends the INSERT into syntax, allowing multiple rows to be inserted at once. As follows:
Insert into table name (Field 1, Field 2, Field 3)
Values (the value of field 1 is 1, the value of field 2 is 1, the value of field 3 is 1), (the value of field 1 is 2, the value of field 2 is 2, and the value of field 3 is 2),...

6 Pat Field

and query fields: 1-Pet Category 2-Origin 3-trade place 4--age 5--fur Color