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number of characters after b. A couple of interesting variations of the criterion expression can search for all rows whose LastName column value ends with b (%b) or contains b (%b%). In addition, you are not restricted to using a single character (b) you can also use any string of characters. SELECT FirstName, LastName, EmailAddress, Phone FROM Person.Contact WHERE LastName LIKE 'b%' Using a local variable with a wildcard character as an expression for a WHERE clause makes it easy to change a search criterion for a column of character values. When you specify such an expression for a WHERE clause, you need to use the concatenation operator (+) to merge the wildcard character with the local variable. The SELECT statement that follows illustrates how to use the concatenation operator following a local variable (@alpha) to merge the variable with a wildcard character. By declaring the local variable with an nchar(1) data type, you enable searches that begin with just one character. If you want to permit searches that begin with a variable number of characters, such as up to 10, you can declare the local variable with either nvarchar(10) or varchar(10). DECLARE @alpha nchar(1) SET @alpha = 'b' SELECT FirstName, LastName, EmailAddress, Phone FROM Person.Contact WHERE LastName LIKE @alpha + '%' The preceding sample is interesting because it suggests so many useful extensions. For example, instead of searching for LastName column values that begin with a character, you can switch the order of the wildcard character and the local variable in the WHERE clause of a SELECT statement to return rows that end with a character. In addition, you aren t restricted to using just one local variable. The following SELECT statement includes a WHERE clause that searches for rows that start with one character and end with another. In this case, the beginning character is c and the ending character is o. The use of the % wildcard character is very powerful in this and other searches for a string of characters because % matches any number of characters. By modifying the SET statements assigning values to @alpha and @endalpha, you can search for LastName column values with different beginning and ending characters. DECLARE @alpha nchar(1), @endalpha nchar(1) SET @alpha = 'c' SET @endalpha = 'o' SELECT FirstName, LastName, EmailAddress, Phone FROM Person.Contact WHERE LastName LIKE @alpha + '%' + @endalpha Aside from just searching for values that begin or end with one or more characters, you can also use the LIKE operator and the % wildcard character to represent the notion of contained in. You can represent this notion by embedding a local variable between two wildcard characters. The WHERE clause in the following SELECT statement returns rows whose LastName column values contain bell either at the beginning, in the middle, or at the end of the string of characters within the column. DECLARE @alpha nvarchar(10) SET @alpha = 'bell' SELECT FirstName, LastName, EmailAddress, Phone FROM Person.Contact WHERE LastName LIKE '%' + @alpha + '%' To emphasize how flexible this kind of formulation is, an excerpt showing the first 10 rows from the result set returned by the preceding SELECT statement appears next. The first row shows bell beginning a LastName column value. The next three rows show bell at the end of their LastName

column values. The fifth row has bell embedded with its name. The 10th row shows bell as the whole LastName column value. In this case, the beginning and ending wildcard characters represent a character string of zero length. FirstName --------Shane Joan David Frank Deanna David John John Jean Alexandra LastName -------Belli Campbell Campbell Campbell Sabella Campbell Campbell Campbell Campbell Bell EmailAddress -----------------------------shane1@adventure-works.com joan0@adventure-works.com david14@adventure-works.com frank4@adventure-works.com deanna2@adventure-works.com david8@adventure-works.com john0@adventure-works.com john30@adventure-works.com jean7@adventure-works.com alexandra7@adventure-works.com Phone -----------843-555-0175 700-555-0155 756-555-0117 491-555-0132 529-555-0100 740-555-0182 435-555-0113 593-555-0100 827-555-0100 987-555-0181

There are many ways in which you can combine exact and approximate matches for different column values. The following SELECT statement includes two expressions in its WHERE clause. The first expression specifies an exact search (LastName column value must equal Blanco), and the second expression designates an approximate search (Phone column value includes a country code of (11)). The AND operator between the two expressions additionally requires that rows in the result set must satisfy both expressions instead of just either expression or even neither expression. DECLARE @alpha1 nvarchar(30), @alpha2 nvarchar(10) SET @alpha1 = 'Blanco' SET @alpha2 = '%(11)%' SELECT FirstName, LastName, EmailAddress, Phone FROM Person.Contact WHERE LastName = @alpha1 AND Phone LIKE @alpha2