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Next, it sets the parameter to 1 (from the Integer passed to queryForObject() as
the second parameter above), and finally executes the prepared statement. It
then takes the resulting row, maps it to an object, and returns it.
While this may seem like low-level information, it is important to understand
what is happening here. One of the most frequently asked questions regarding
i BATIS is: “How do I use LIKE in my WHERE clauses?” Looking at the previous state-
ment, it is obvious why the parameter that is coming in has to have the wildcards
in it, and why they cannot be inserted into the SQL statement easily. There are
three possible solutions to that dilemma:
The value of the parameter passed in has to have the SQL wildcard charac-
ters in it.
The text to search for has to be part of a SQL expression (e.g., '%' ||
#value# || '%' ) that can be parameterized.
The substitution syntax (which is the next topic, in section 4.2.2) has to be
used instead.
Using inline parameters with the $ placeholders
Another way to use inline parameters is with the substitution ($) syntax, which is
used to insert a value directly into the SQL before it is turned into a parameterized
statement. Use this approach with caution, as it may leave you open to SQL injection, and
it may cause performance problems if overused.
This is one approach to handling LIKE operators. Here is an example:
<select id="getByLikeCity" resultClass="Account">
from Account
where city like '%$value$%'
The difference between this statement and the last one is how i BATIS handles the
parameter passed into the statement. This statement is called the same way:
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