Data

Question 1

SELECT statement example

Answer 1

• SELECT [columms]
• FROM [tables]
• WHERE [search_condition]
• ORDER BY [order_expresssion ASC | DESC]

Question 2

WHERE with text values

Answer 2

• Requires apostrophes around the value
• Example:
  
  • ‘XX’

Question 3

WHERE additional operators

Answer 3

• AND
• <
• >
• LIKE

Question 4

• All strings that start with X
• All strings that end with X
• All strings that contain with X
• All strings that start with X, Y or Z

Answer 4

• LIKE ‘X%’
• LIKE ‘%X’
• LIKE ‘%X%’
• LIKE ‘[XYZ]’

Question 5

SQL aggregate functions

Answer 5

• AVG - Returns the average value
• COUNT - Returns the number of rows
• FIRST - Returns the first value
• LAST - Returns the last value
• MAX - Returns the largest value
• MIN - Returns the smallest value
• SUM - Returns the sum

Question 6

SQL scalar functions

Answer 6

• UCASE - Converts a field to upper case
• LCASE - Converts a field to lower case
• MID - Extract characters from a text field
• LEN - Returns the length of a text field
• ROUND - Rounds a numeric field to the number of decimals specified
• NOW - Returns the current system date and time
• FORMAT - Formats how a field is to be displayed

Question 7

UPDATE statement example

Answer 7

• UPDATE [table]
• SET [update_expression]
• WHERE [search_condition]

Question 8

INSERT statement example

Answer 8

• INSERT INTO [table] ([colum_list])
• VALUES ([value_list])

Question 9

DELETE statement example

Answer 9

• DELETE FROM [table]
• WHERE [search_condition]

Question 10

ADO.NET Namespaces for SQL Server Data Access

Answer 10

• System.Data.SqlClient
• System.Data.SqlTypes
• System.Data

Question 11

How to insert a backslash

(C# assumes that every backslash is the start fo a special character)

Answer 11

• Use two backslash: \
• Put the @ character before the entire string: @”string”