Develop Reference

How to use Regex keyword in Spring Data Repository Method

I am currently using spring-data-jpa version 1.9.4.
I have a MySql table with columns project(integer), summary(varchar), and description(varchar).
I have a regex that I would like to use to search the summary and/or description field meaning that if it finds it in summary does not need to apply regex to description.
The repository method I am attempting to use is:
List<Issue> findByProjectAndSummaryOrDescriptionRegex(long project, String regex)
The error I am receiving is:
java.lang.IllegalArgumentException: Unsupported keyword REGEX (1):
[MatchesRegex, Matches, Regex]
It is difficult in my company environment to update/upgrade versions, so if the issue is NOT my syntax but rather the then if someone knows which version now supports 'Regex' for query derivation or where I could find that specific information I would be grateful. I have looked at the Changelog and it appears that 1.9.4 should support but it appears not.
Thanks for your help!
JD
EDIT 1: I am aware of the #Query annotation but have been asked by my lead to only use that as a last resort if I cannot find the correct version which supports keyword REGEX [MatchesRegex, Matches, Regex]

I would recommend using native query (with #Query annotation) if the Spring data syntax does not work, e.g.:
#Query(nativeQuery=true, value="SELECT * FROM table WHERE project = ?1 AND (summary regexp ?2 OR description regexp ?2)")
List<Issue> findByProjectAndSummaryOrDescription(long project, String regex);
Update
If native query is not an option then (a) could you try it with single column and see if that works and (b) could you try by appending regex to both the columns, e.g.:
List<Issue> findByProjectAndDescriptionRegex(long project, String regex);
List<Issue> findByProjectAndSummaryRegexOrDescriptionRegex(long project, String regex, String regex);

In a followup, I discovered by doing some digging that the authoratative list will reside in the org.springframework.data.jpa.repository.query.JpaQueryCreator class. So for future folks that want to know which keywords from the 'Documented' list are ACTUALLY implemented, look inside JpaQueryCreator and you will the keywords supported as case arguments inside a switch!
Hope this helps!
PS - as suspected, REGEX was not supported in my version

try tu use #Query with param nativeQuery = true inside You can use database regexp_like function :
#Query(value = "select t.* from TABLE_NAME t where regexp_like(t.column, ?1)", nativeQuery = true)
Documentation :
https://www.techonthenet.com/oracle/regexp_like.php

Mockrunner(Java) query with Regex

I am using Mockrunner to mock Sql DB for my unit tests. Following is my query:-
"select * from table where userId in (" + userIds + ")"
Now my userIds is state dependent. I don't need my test cases dependent on the arrangement inside the list - userIds. So I don't need exact match but regex matching. I have already enabled regex matching by below code:-
StatementResultSetHandler statementHandler = connection.getStatementResultSetHandler();
usersResult = statementHandler.createResultSet("users");
statementHandler.setUseRegularExpressions(true);
//How to write this regex query?
statementHandler.prepareResultSet("select * from table where userId in .*", campaignsResult);
But as it is noted, I have no idea about the regex syntax supported by Mockrunner.
Edit: I unable to match queries like "Select * from tables" with "Select * from tab .*". So It has to do something with the way I using regex with Mockrunner

There are some helpful examples available here. For instance:
public void testCorrectSQL() throws Exception {
MockResultSet result = getStatementResultSetHandler().createResultSet();
getStatementResultSetHandler().prepareResultSet("select.*isbn,.*quantity.*", result);
List orderList = new ArrayList();
orderList.add("1234567890");
orderList.add("1111111111");
Bookstore.order(getJDBCMockObjectFactory().getMockConnection(), orderList);
verifySQLStatementExecuted("select.*isbn,.*quantity.*\\(isbn='1234567890'.*or.*isbn='1111111111'\\)");
}
From this, I surmise that it's using standard Java regex syntax. In which case, you probably want:
prepareResultSet("select \\* from table where userId in \\(.*\\)", campaignsResult);
...or perhaps more succinctly (and depending upon exactly how fine-grained your tests need to be):
prepareResultSet("select .* from table where userId in .*", campaignsResult);
The main caveat to be aware of when enabling the regex matching is that any literal special characters that you want in your query (such as *, (, and ) literals) need to be escaped in your regex before it will work properly.

appengine datastore query escaping single quote (')

I have used javax.jdo.Query like here JDO for Google App Engine: escaping quotes. Yet, my query string with single quote (') keep getting exploded.
Query query = pm.newQuery("select from " + Book.class.getName() + " where mArtist== '"+ artist + "' && mTitle=='" + title + "'");
Here is the exception
javax.jdo.JDOUserException: Portion of expression could not be parsed: 't Give Up'
org.datanucleus.store.query.QueryCompilerSyntaxException: Portion of expression could not be parsed: 't Give Up'
Here is this query.toString()
SELECT FROM com.example.Book WHERE mArtist== 'Famous Writer' && mTitle=='We Won''t Give Up'
Yeh, I have even escaped the single quote(') with double single quote per appengine docs
a str literal, as a single-quoted string. Single-quote characters in the string must be escaped as ''. For example: 'Joe''s Diner'

Building a query by string concatenation is almost always a risky thing to do, even when SQL Injection attacks aren't possible. (They aren't with GAE.)
See http://code.google.com/appengine/docs/java/datastore/jdo/queries.html#Introducing_Queries and note the bit on "parameter substitution".

The example code in the document only cover a single parameter substitution. Here is a bit more.
Query query = pm.newQuery(Book.class);
query.setFilter("mArtist == artist && mTitle == title");
query.declareParameters("String artist,String title");
List<Book> list = (List<Book>) query.execute("Famous Writer","We Won't Give Up");
Some SO questions worth reading :
How to dynamically build JDO Queries on multiple parameters
Google Datastore problem with query on *User* type

Using LIKE operator in Access works but not in Java

I'm making a java application for a toy store and using the MS-Access database.
I'm using the operator "LIKE" to search for products in database using the user's keyword.
E.g. in Access:
SELECT * FROM tblToy WHERE toyName LIKE '*puppy*' OR toyBrand LIKE '*puppy*'
this gives me the desired result in access.
But in java when i run this same query it returns null:
String query = "puppy";
sql = "SELECT * FROM tblToy WHERE toyName LIKE '*" + query+"*' "+
"OR toyBrand LIKE '*" + query + "*'";
rs = db.executeQuery(sql);
while(rs.next()){
String name = rs.getString("toyName");
return name;
}
return null;
Can anyone help me on this? I know it must be something simple which I'm missing out now but I just don't know what to do. Would appreciate your guys help.

I think with Java, you need to escape single quotes, so try using \' for all your single quotes, then try % instead of * as someone else mentioned, since % is the wildcard for SQL.

There are two possibilities for wildcards according to where you are running the query, * or %. In this case, you need %

JAVA: NamedQuery String problem

Hello guys I am having some problems with exact matches while doing a NamedQuery.
I am currently using something like this:
#NamedQuery(name = MyClass.GET_ENTRY_BY_NAME, query = "select e from Entry e where e.name =:"+ Entry.NAME )
...
Query query = em.createNamedQuery(MyClass.GET_ENTRY_BY_NAME);
query.setParameter(Entry.NAME, myEntry.getName());
It works for most cases, however I noticed that in case the user pass the file name with an space at the end, the namedQuery ignores that character. For example:
Query query = em.createNamedQuery(MyClass.GET_ENTRY_BY_NAME);
query.setParameter(Entry.NAME, myEntry.getName()+ " ");
Will return the same result as the query before. Bypassing my 'valid entry' validation. In other words I'd like the query to return no entry at all and treat the error later on.
One workaround I could think of, is to put single quotes surrounding my parameter in the namedQuery, like this:
#NamedQuery(name = MyClass.GET_ENTRY_BY_NAME, query = "select e from entry e where e.name =':"+ Entry.NAME "'")
However it will trash my code in case the String contains single quotes in it...
Any ideas guys?

I guess this happens because your database field is declared as CHAR(...), and therefore stored values are padded with whitespaces which are not taken into account by = operation.
So, you may either declare your database field as VARCHAR(...) or use a built-in trim function:
query = "select e from Entry e where trim(trailing from e.name) =:"+ Entry.NAME

I did some research in JPA and found out that it does some automatic trimming for CHARs, I am not sure if this behaves the same with Strings, but since it is happening to me... I believe so. The only way to bypass it is by setting some attribute within the session DatabaseLogin object (see http://www.eclipse.org/eclipselink/api/1.1/org/eclipse/persistence/sessions/DatabaseLogin.html#setShouldTrimStrings) .
Well I didn't want to be messing up with the session properties so I decided to make some sort of check and throwing the same exception as the NoResultException catch does in my code.
I basically took the result from the database and compared the field with the String I used:
query.setParameter(Entry.NAME, myEntry.getName());
...
if(!StringUtils.equals(result.getName(), myEntry.getName()){
do a cool throw just like NoResultException Catch
}
I also had to include the Trim function axtavt! This is just to make sure that if the database has a column with trailing spaces and it matches the parameter given by the user, it will be included as a valid answer. For example:
Database entry: Name = "Flavio " - Trimmed with Function = "Flavio".
Parameter passed: Name = "Flavio " - Trimmed by JPA automatic function = "Flavio".
If it isnt trimmed at all it will just Compare "Flavio " with "Flavio", returning NoResult when it was supposed to return that Entry.
Nasty workaround, but as long as there is no other way to stop the auto-trimming we will have to just make use of this sort of things.
Thanks for all the other answers!!