CODEWITHSUNDEEP
ignitegridgain
sridhar
sridhar

Reputation: 31

ignite query cache with value as list of objects

I am using ignite cache with key as String and value as Collection of objects (similar type) say List.

Now i would like to query on the students stored in cache let's say 5 top scored students.

defined the configuration as below

CacheConfiguration<String, List<Student>> cfg = new CacheConfiguration<String, List<Student>>("students");
ignite = Ignition.start("/usr/localc/ignite/examples/config/example-ignite.xml");
cfg.setIndexedTypes(String.class, List.class);

Now I fired a query like

SqlFieldsQuery qry = new SqlFieldsQuery("select count(*) from Person");

Then got exception like

Exception in thread "main" java.lang.AbstractMethodError: org.apache.ignite.internal.processors.query.h2.opt.GridH2Table$ScanIndex.getCost(Lorg/h2/engine/Session;[I[Lorg/h2/table/TableFilter;ILorg/h2/result/SortOrder;Ljava/util/HashSet;)D
at org.h2.table.TableFilter.getBestPlanItem(TableFilter.java:203)
at org.h2.table.Plan.calculateCost(Plan.java:123)
at org.h2.command.dml.Optimizer.testPlan(Optimizer.java:183)
at org.h2.command.dml.Optimizer.calculateBestPlan(Optimizer.java:79)
at org.h2.command.dml.Optimizer.optimize(Optimizer.java:242)
at org.h2.command.dml.Select.preparePlan(Select.java:1014)
at org.h2.command.dml.Select.prepare(Select.java:878)
at org.h2.command.Parser.prepareCommand(Parser.java:259)
at org.h2.engine.Session.prepareLocal(Session.java:560)
at org.h2.engine.Session.prepareCommand(Session.java:501)
at org.h2.jdbc.JdbcConnection.prepareCommand(JdbcConnection.java:1202)
at org.h2.jdbc.JdbcPreparedStatement.<init>(JdbcPreparedStatement.java:73)
at org.h2.jdbc.JdbcConnection.prepareStatement(JdbcConnection.java:290)
at org.apache.ignite.internal.processors.query.h2.IgniteH2Indexing.prepareStatement(IgniteH2Indexing.java:406)
at org.apache.ignite.internal.processors.query.h2.IgniteH2Indexing.queryTwoStep(IgniteH2Indexing.java:1121)
at org.apache.ignite.internal.processors.query.GridQueryProcessor$2.applyx(GridQueryProcessor.java:732)
at org.apache.ignite.internal.processors.query.GridQueryProcessor$2.applyx(GridQueryProcessor.java:730)
at org.apache.ignite.internal.util.lang.IgniteOutClosureX.apply(IgniteOutClosureX.java:36)
at org.apache.ignite.internal.processors.query.GridQueryProcessor.executeQuery(GridQueryProcessor.java:1666)
at org.apache.ignite.internal.processors.query.GridQueryProcessor.queryTwoStep(GridQueryProcessor.java:730)
at org.apache.ignite.internal.processors.cache.IgniteCacheProxy.query(IgniteCacheProxy.java:700)
at com.tcs.enm.processor.Main.main(Main.java:47)

Can any one help me how to query ???

Upvotes: 3

Views: 1630

Answers (2)

Victor3y
Victor3y

Reputation: 886

For anyone in the future who has this issue, this error message is likely due to using an incorrect version of H2.

http://apache-ignite-users.70518.x6.nabble.com/Exception-while-trying-to-access-cache-via-JDBC-API-td8648.html#a8651

If you're using Ignite 1.7, you need h2database 1.4.191. Note that h2database 1.4.192 WILL give you the exception in the question because there are some changes in 192 which Ignite wasn't made to handle

I went through my packages and changed the H2 version to 1.4.191 and it fixed my problems.

Upvotes: 1

Valentin Kulichenko
Valentin Kulichenko

Reputation: 8390

To execute such query you should store each Student as a separate entry. Student class should have all the annotations defining fields and indexes and the cache configuration should look like this:

cfg.setIndexedTypes(String.class, Student.class);

For more details refer to this documentation: https://apacheignite.readme.io/docs/sql-queries

Upvotes: 3

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