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Posted to commits@cassandra.apache.org by br...@apache.org on 2012/02/14 00:44:29 UTC
[3/3] git commit: Pig: inferred and actual schema match,
smoke tests. Patch by brandonwilliams, reviewed by xedin for CASSANDRA-3371
Pig: inferred and actual schema match, smoke tests.
Patch by brandonwilliams, reviewed by xedin for CASSANDRA-3371
Project: http://git-wip-us.apache.org/repos/asf/cassandra/repo
Commit: http://git-wip-us.apache.org/repos/asf/cassandra/commit/e48b29a6
Tree: http://git-wip-us.apache.org/repos/asf/cassandra/tree/e48b29a6
Diff: http://git-wip-us.apache.org/repos/asf/cassandra/diff/e48b29a6
Branch: refs/heads/trunk
Commit: e48b29a6b0b15f9e1c8d8e462a573daa04d1ec5e
Parents: 9ca8478
Author: Brandon Williams <br...@apache.org>
Authored: Mon Feb 13 17:28:47 2012 -0600
Committer: Brandon Williams <br...@apache.org>
Committed: Mon Feb 13 17:28:47 2012 -0600
----------------------------------------------------------------------
.../cassandra/hadoop/pig/CassandraStorage.java | 304 +++++++++------
contrib/pig/test/populate-cli.txt | 67 ++++
contrib/pig/test/test_storage.pig | 22 +
3 files changed, 283 insertions(+), 110 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/cassandra/blob/e48b29a6/contrib/pig/src/java/org/apache/cassandra/hadoop/pig/CassandraStorage.java
----------------------------------------------------------------------
diff --git a/contrib/pig/src/java/org/apache/cassandra/hadoop/pig/CassandraStorage.java b/contrib/pig/src/java/org/apache/cassandra/hadoop/pig/CassandraStorage.java
index 975d5ba..7e55ee0 100644
--- a/contrib/pig/src/java/org/apache/cassandra/hadoop/pig/CassandraStorage.java
+++ b/contrib/pig/src/java/org/apache/cassandra/hadoop/pig/CassandraStorage.java
@@ -26,6 +26,7 @@ import org.apache.cassandra.db.marshal.BytesType;
import org.apache.cassandra.db.marshal.IntegerType;
import org.apache.cassandra.db.marshal.TypeParser;
import org.apache.cassandra.thrift.*;
+import org.apache.cassandra.utils.FBUtilities;
import org.apache.cassandra.utils.Hex;
import org.apache.cassandra.utils.UUIDGen;
import org.apache.commons.logging.Log;
@@ -33,7 +34,6 @@ import org.apache.commons.logging.LogFactory;
import org.apache.cassandra.db.Column;
import org.apache.cassandra.db.IColumn;
-import org.apache.cassandra.db.SuperColumn;
import org.apache.cassandra.db.marshal.*;
import org.apache.cassandra.hadoop.*;
import org.apache.cassandra.thrift.Mutation;
@@ -50,15 +50,10 @@ import org.apache.pig.backend.executionengine.ExecException;
import org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigSplit;
import org.apache.pig.data.*;
import org.apache.pig.ResourceSchema.ResourceFieldSchema;
-import org.apache.pig.impl.logicalLayer.FrontendException;
import org.apache.pig.impl.util.UDFContext;
import org.apache.thrift.TDeserializer;
import org.apache.thrift.TException;
import org.apache.thrift.TSerializer;
-import org.apache.thrift.transport.TFramedTransport;
-import org.apache.thrift.transport.TSocket;
-import org.apache.thrift.transport.TTransport;
-import org.apache.thrift.transport.TTransportException;
/**
* A LoadStoreFunc for retrieving data from and storing data to Cassandra
@@ -85,8 +80,8 @@ public class CassandraStorage extends LoadFunc implements StoreFuncInterface, Lo
private String storeSignature;
private Configuration conf;
- private RecordReader reader;
- private RecordWriter writer;
+ private RecordReader<ByteBuffer, Map<ByteBuffer, IColumn>> reader;
+ private RecordWriter<ByteBuffer, List<Mutation>> writer;
private int limit;
public CassandraStorage()
@@ -118,20 +113,37 @@ public class CassandraStorage extends LoadFunc implements StoreFuncInterface, Lo
return null;
CfDef cfDef = getCfDef(loadSignature);
- ByteBuffer key = (ByteBuffer)reader.getCurrentKey();
- SortedMap<ByteBuffer,IColumn> cf = (SortedMap<ByteBuffer,IColumn>)reader.getCurrentValue();
+ ByteBuffer key = reader.getCurrentKey();
+ Map<ByteBuffer, IColumn> cf = reader.getCurrentValue();
assert key != null && cf != null;
-
- // and wrap it in a tuple
- Tuple tuple = TupleFactory.getInstance().newTuple(2);
- ArrayList<Tuple> columns = new ArrayList<Tuple>();
- tuple.set(0, new DataByteArray(key.array(), key.position()+key.arrayOffset(), key.limit()+key.arrayOffset()));
+
+ // output tuple, will hold the key, each indexed column in a tuple, then a bag of the rest
+ Tuple tuple = TupleFactory.getInstance().newTuple();
+ DefaultDataBag bag = new DefaultDataBag();
+ // set the key
+ tuple.append(new DataByteArray(ByteBufferUtil.getArray(key)));
+ // we must add all the indexed columns first to match the schema
+ Map<ByteBuffer, Boolean> added = new HashMap<ByteBuffer, Boolean>();
+ // take care to iterate these in the same order as the schema does
+ for (ColumnDef cdef : cfDef.column_metadata)
+ {
+ if (cf.containsKey(cdef.name))
+ {
+ tuple.append(columnToTuple(cf.get(cdef.name), cfDef, parseType(cfDef.getComparator_type())));
+ }
+ else
+ { // otherwise, we need to add an empty tuple to take its place
+ tuple.append(TupleFactory.getInstance().newTuple());
+ }
+ added.put(cdef.name, true);
+ }
+ // now add all the other columns
for (Map.Entry<ByteBuffer, IColumn> entry : cf.entrySet())
{
- columns.add(columnToTuple(entry.getValue(), cfDef, parseType(cfDef.getComparator_type())));
+ if (!added.containsKey(entry.getKey()))
+ bag.add(columnToTuple(entry.getValue(), cfDef, parseType(cfDef.getComparator_type())));
}
-
- tuple.set(1, new DefaultDataBag(columns));
+ tuple.append(bag);
return tuple;
}
catch (InterruptedException e)
@@ -334,6 +346,8 @@ public class CassandraStorage extends LoadFunc implements StoreFuncInterface, Lo
}
ConfigHelper.setInputColumnFamily(conf, keyspace, column_family);
setConnectionInformation();
+ if (loadSignature == null)
+ loadSignature = location;
initSchema(loadSignature);
}
@@ -344,6 +358,13 @@ public class CassandraStorage extends LoadFunc implements StoreFuncInterface, Lo
if (cfDef.column_type.equals("Super"))
return null;
+ /*
+ Our returned schema should look like this:
+ (key, index1:(name, value), index2:(name, value), columns:{(name, value)})
+ Which is to say, columns that have metadata will be returned as named tuples, but unknown columns will go into a bag.
+ This way, wide rows can still be handled by the bag, but known columns can easily be referenced.
+ */
+
// top-level schema, no type
ResourceSchema schema = new ResourceSchema();
@@ -356,54 +377,59 @@ public class CassandraStorage extends LoadFunc implements StoreFuncInterface, Lo
keyFieldSchema.setName("key");
keyFieldSchema.setType(getPigType(marshallers.get(2)));
- // will become the bag of tuples
- ResourceFieldSchema bagFieldSchema = new ResourceFieldSchema();
- bagFieldSchema.setName("columns");
- bagFieldSchema.setType(DataType.BAG);
ResourceSchema bagSchema = new ResourceSchema();
-
- List<ResourceFieldSchema> tupleFields = new ArrayList<ResourceFieldSchema>();
-
- // default comparator/validator
- ResourceSchema innerTupleSchema = new ResourceSchema();
- ResourceFieldSchema tupleField = new ResourceFieldSchema();
- tupleField.setType(DataType.TUPLE);
- tupleField.setSchema(innerTupleSchema);
-
- ResourceFieldSchema colSchema = new ResourceFieldSchema();
- colSchema.setName("name");
- colSchema.setType(getPigType(marshallers.get(0)));
- tupleFields.add(colSchema);
-
- ResourceFieldSchema valSchema = new ResourceFieldSchema();
- AbstractType validator = marshallers.get(1);
- valSchema.setName("value");
- valSchema.setType(getPigType(validator));
- tupleFields.add(valSchema);
+ ResourceFieldSchema bagField = new ResourceFieldSchema();
+ bagField.setType(DataType.BAG);
+ bagField.setName("columns");
+ // inside the bag, place one tuple with the default comparator/validator schema
+ ResourceSchema bagTupleSchema = new ResourceSchema();
+ ResourceFieldSchema bagTupleField = new ResourceFieldSchema();
+ bagTupleField.setType(DataType.TUPLE);
+ ResourceFieldSchema bagcolSchema = new ResourceFieldSchema();
+ ResourceFieldSchema bagvalSchema = new ResourceFieldSchema();
+ bagcolSchema.setName("name");
+ bagvalSchema.setName("value");
+ bagcolSchema.setType(getPigType(marshallers.get(0)));
+ bagvalSchema.setType(getPigType(marshallers.get(1)));
+ bagTupleSchema.setFields(new ResourceFieldSchema[] { bagcolSchema, bagvalSchema });
+ bagTupleField.setSchema(bagTupleSchema);
+ bagSchema.setFields(new ResourceFieldSchema[] { bagTupleField });
+ bagField.setSchema(bagSchema);
+
+ // will contain all fields for this schema
+ List<ResourceFieldSchema> allSchemaFields = new ArrayList<ResourceFieldSchema>();
+ // add the key first, then the indexed columns, and finally the bag
+ allSchemaFields.add(keyFieldSchema);
// defined validators/indexes
for (ColumnDef cdef : cfDef.column_metadata)
{
- colSchema = new ResourceFieldSchema();
- colSchema.setName(new String(cdef.getName()));
- colSchema.setType(getPigType(marshallers.get(0)));
- tupleFields.add(colSchema);
-
- valSchema = new ResourceFieldSchema();
- validator = validators.get(ByteBuffer.wrap(cdef.getName()));
+ // make a new tuple for each col/val pair
+ ResourceSchema innerTupleSchema = new ResourceSchema();
+ ResourceFieldSchema innerTupleField = new ResourceFieldSchema();
+ innerTupleField.setType(DataType.TUPLE);
+ innerTupleField.setSchema(innerTupleSchema);
+ innerTupleField.setName(new String(cdef.getName()));
+
+ ResourceFieldSchema idxColSchema = new ResourceFieldSchema();
+ idxColSchema.setName("name");
+ idxColSchema.setType(getPigType(marshallers.get(0)));
+
+ ResourceFieldSchema valSchema = new ResourceFieldSchema();
+ AbstractType validator = validators.get(cdef.name);
if (validator == null)
validator = marshallers.get(1);
valSchema.setName("value");
valSchema.setType(getPigType(validator));
- tupleFields.add(valSchema);
+
+ innerTupleSchema.setFields(new ResourceFieldSchema[] { idxColSchema, valSchema });
+ allSchemaFields.add(innerTupleField);
}
- innerTupleSchema.setFields(tupleFields.toArray(new ResourceFieldSchema[tupleFields.size()]));
+ // bag at the end for unknown columns
+ allSchemaFields.add(bagField);
- // a bag can contain only one tuple, but that tuple can contain anything
- bagSchema.setFields(new ResourceFieldSchema[] { tupleField });
- bagFieldSchema.setSchema(bagSchema);
// top level schema contains everything
- schema.setFields(new ResourceFieldSchema[] { keyFieldSchema, bagFieldSchema });
+ schema.setFields(allSchemaFields.toArray(new ResourceFieldSchema[allSchemaFields.size()]));
return schema;
}
@@ -502,79 +528,137 @@ public class CassandraStorage extends LoadFunc implements StoreFuncInterface, Lo
return DoubleType.instance.decompose((Double)o);
if (o instanceof UUID)
return ByteBuffer.wrap(UUIDGen.decompose((UUID) o));
+
return ByteBuffer.wrap(((DataByteArray) o).get());
}
- public void putNext(Tuple t) throws ExecException, IOException
+ public void putNext(Tuple t) throws IOException
{
+ /*
+ We support two cases for output:
+ First, the original output:
+ (key, (name, value), (name,value), {(name,value)}) (tuples or bag is optional)
+ For supers, we only accept the original output.
+ */
+
+ if (t.size() < 1)
+ {
+ // simply nothing here, we can't even delete without a key
+ logger.warn("Empty output skipped, filter empty tuples to suppress this warning");
+ return;
+ }
ByteBuffer key = objToBB(t.get(0));
- DefaultDataBag pairs = (DefaultDataBag) t.get(1);
+ if (t.getType(1) == DataType.TUPLE)
+ writeColumnsFromTuple(key, t, 1);
+ else if (t.getType(1) == DataType.BAG)
+ {
+ if (t.size() > 2)
+ throw new IOException("No arguments allowed after bag");
+ writeColumnsFromBag(key, (DefaultDataBag) t.get(1));
+ }
+ else
+ throw new IOException("Second argument in output must be a tuple or bag");
+ }
+
+ private void writeColumnsFromTuple(ByteBuffer key, Tuple t, int offset) throws IOException
+ {
ArrayList<Mutation> mutationList = new ArrayList<Mutation>();
- CfDef cfDef = getCfDef(storeSignature);
- try
+ for (int i = offset; i < t.size(); i++)
{
- for (Tuple pair : pairs)
+ if (t.getType(i) == DataType.BAG)
+ writeColumnsFromBag(key, (DefaultDataBag) t.get(i));
+ else if (t.getType(i) == DataType.TUPLE)
{
- Mutation mutation = new Mutation();
- if (DataType.findType(pair.get(1)) == DataType.BAG) // supercolumn
- {
- org.apache.cassandra.thrift.SuperColumn sc = new org.apache.cassandra.thrift.SuperColumn();
- sc.name = objToBB(pair.get(0));
- ArrayList<org.apache.cassandra.thrift.Column> columns = new ArrayList<org.apache.cassandra.thrift.Column>();
- for (Tuple subcol : (DefaultDataBag) pair.get(1))
- {
- org.apache.cassandra.thrift.Column column = new org.apache.cassandra.thrift.Column();
- column.name = objToBB(subcol.get(0));
- column.value = objToBB(subcol.get(1));
- column.setTimestamp(System.currentTimeMillis() * 1000);
- columns.add(column);
- }
- if (columns.isEmpty()) // a deletion
- {
- mutation.deletion = new Deletion();
- mutation.deletion.super_column = objToBB(pair.get(0));
- mutation.deletion.setTimestamp(System.currentTimeMillis() * 1000);
- }
- else
- {
- sc.columns = columns;
- mutation.column_or_supercolumn = new ColumnOrSuperColumn();
- mutation.column_or_supercolumn.super_column = sc;
- }
- }
- else // assume column since it couldn't be anything else
- {
- if (pair.get(1) == null)
- {
- mutation.deletion = new Deletion();
- mutation.deletion.predicate = new org.apache.cassandra.thrift.SlicePredicate();
- mutation.deletion.predicate.column_names = Arrays.asList(objToBB(pair.get(0)));
- mutation.deletion.setTimestamp(System.currentTimeMillis() * 1000);
- }
- else
- {
- org.apache.cassandra.thrift.Column column = new org.apache.cassandra.thrift.Column();
- column.name = objToBB(pair.get(0));
- column.value = objToBB(pair.get(1));
- column.setTimestamp(System.currentTimeMillis() * 1000);
- mutation.column_or_supercolumn = new ColumnOrSuperColumn();
- mutation.column_or_supercolumn.column = column;
- }
- }
- mutationList.add(mutation);
+ Tuple inner = (Tuple) t.get(i);
+ if (inner.size() > 0) // may be empty, for an indexed column that wasn't present
+ mutationList.add(mutationFromTuple(inner));
}
+ else
+ throw new IOException("Output type was not a bag or a tuple");
}
- catch (ClassCastException e)
+ if (mutationList.size() > 0)
+ writeMutations(key, mutationList);
+ }
+
+ private Mutation mutationFromTuple(Tuple t) throws IOException
+ {
+ Mutation mutation = new Mutation();
+ if (t.get(1) == null)
{
- throw new IOException(e + " Output must be (key, {(column,value)...}) for ColumnFamily or (key, {supercolumn:{(column,value)...}...}) for SuperColumnFamily", e);
+ // TODO: optional deletion
+ mutation.deletion = new Deletion();
+ mutation.deletion.predicate = new org.apache.cassandra.thrift.SlicePredicate();
+ mutation.deletion.predicate.column_names = Arrays.asList(objToBB(t.get(0)));
+ mutation.deletion.setTimestamp(FBUtilities.timestampMicros());
}
+ else
+ {
+ org.apache.cassandra.thrift.Column column = new org.apache.cassandra.thrift.Column();
+ column.setName(objToBB(t.get(0)));
+ column.setValue(objToBB(t.get(1)));
+ column.setTimestamp(FBUtilities.timestampMicros());
+ mutation.column_or_supercolumn = new ColumnOrSuperColumn();
+ mutation.column_or_supercolumn.column = column;
+ }
+ return mutation;
+ }
+
+ private void writeColumnsFromBag(ByteBuffer key, DefaultDataBag bag) throws IOException
+ {
+ List<Mutation> mutationList = new ArrayList<Mutation>();
+ for (Tuple pair : bag)
+ {
+ Mutation mutation = new Mutation();
+ if (DataType.findType(pair.get(1)) == DataType.BAG) // supercolumn
+ {
+ SuperColumn sc = new SuperColumn();
+ sc.setName(objToBB(pair.get(0)));
+ List<org.apache.cassandra.thrift.Column> columns = new ArrayList<org.apache.cassandra.thrift.Column>();
+ for (Tuple subcol : (DefaultDataBag) pair.get(1))
+ {
+ org.apache.cassandra.thrift.Column column = new org.apache.cassandra.thrift.Column();
+ column.setName(objToBB(subcol.get(0)));
+ column.setValue(objToBB(subcol.get(1)));
+ column.setTimestamp(FBUtilities.timestampMicros());
+ columns.add(column);
+ }
+ if (columns.isEmpty()) // TODO: optional deletion
+ {
+ mutation.deletion = new Deletion();
+ mutation.deletion.super_column = objToBB(pair.get(0));
+ mutation.deletion.setTimestamp(FBUtilities.timestampMicros());
+ }
+ else
+ {
+ sc.columns = columns;
+ mutation.column_or_supercolumn = new ColumnOrSuperColumn();
+ mutation.column_or_supercolumn.super_column = sc;
+ }
+ }
+ else
+ mutation = mutationFromTuple(pair);
+ mutationList.add(mutation);
+ // for wide rows, we need to limit the amount of mutations we write at once
+ if (mutationList.size() >= 10) // arbitrary, CFOF will re-batch this up, and BOF won't care
+ {
+ writeMutations(key, mutationList);
+ mutationList.clear();
+ }
+ }
+ // write the last batch
+ if (mutationList.size() > 0)
+ writeMutations(key, mutationList);
+ }
+
+ private void writeMutations(ByteBuffer key, List<Mutation> mutations) throws IOException
+ {
try
{
- writer.write(key, mutationList);
+ writer.write(key, mutations);
}
catch (InterruptedException e)
{
- throw new IOException(e);
+ throw new IOException(e);
}
}
http://git-wip-us.apache.org/repos/asf/cassandra/blob/e48b29a6/contrib/pig/test/populate-cli.txt
----------------------------------------------------------------------
diff --git a/contrib/pig/test/populate-cli.txt b/contrib/pig/test/populate-cli.txt
new file mode 100644
index 0000000..665fba4
--- /dev/null
+++ b/contrib/pig/test/populate-cli.txt
@@ -0,0 +1,67 @@
+create keyspace PigTest;
+use PigTest;
+create column family SomeApp with
+key_validation_class = UTF8Type and
+default_validation_class = LexicalUUIDType and
+comparator = UTF8Type and
+column_metadata =
+[
+ {column_name: name, validation_class: UTF8Type, index_type: KEYS},
+ {column_name: vote_type, validation_class: UTF8Type},
+ {column_name: rating, validation_class: IntegerType},
+ {column_name: score, validation_class: LongType},
+ {column_name: percent, validation_class: FloatType},
+ {column_name: atomic_weight, validation_class: DoubleType},
+];
+
+create column family CopyOfSomeApp with
+key_validation_class = UTF8Type and
+default_validation_class = LexicalUUIDType and
+comparator = UTF8Type and
+column_metadata =
+[
+ {column_name: name, validation_class: UTF8Type, index_type: KEYS},
+ {column_name: vote_type, validation_class: UTF8Type},
+ {column_name: rating, validation_class: IntegerType},
+ {column_name: score, validation_class: LongType},
+ {column_name: percent, validation_class: FloatType},
+ {column_name: atomic_weight, validation_class: DoubleType},
+];
+
+set SomeApp['foo']['name'] = 'User Foo';
+set SomeApp['foo']['vote_type'] = 'like';
+set SomeApp['foo']['rating'] = 8;
+set SomeApp['foo']['score'] = 125000;
+set SomeApp['foo']['percent'] = '85.0';
+set SomeApp['foo']['atomic_weight'] = '2.7182818284590451';
+
+set SomeApp['bar']['name'] = 'User Bar';
+set SomeApp['bar']['vote_type'] = 'like';
+set SomeApp['bar']['rating'] = 9;
+set SomeApp['bar']['score'] = 15000;
+set SomeApp['bar']['percent'] = '35.0';
+set SomeApp['bar']['atomic_weight'] = '3.1415926535897931';
+
+set SomeApp['baz']['name'] = 'User Baz';
+set SomeApp['baz']['vote_type'] = 'dislike';
+set SomeApp['baz']['rating'] = 3;
+set SomeApp['baz']['score'] = 512000;
+set SomeApp['baz']['percent'] = '95.3';
+set SomeApp['baz']['atomic_weight'] = '1.61803399';
+set SomeApp['baz']['extra1'] = lexicaluuid();
+set SomeApp['baz']['extra2'] = lexicaluuid();
+set SomeApp['baz']['extra3'] = lexicaluuid();
+
+set SomeApp['qux']['name'] = 'User Qux';
+set SomeApp['qux']['vote_type'] = 'dislike';
+set SomeApp['qux']['rating'] = 2;
+set SomeApp['qux']['score'] = 12000;
+set SomeApp['qux']['percent'] = '64.7';
+set SomeApp['qux']['atomic_weight'] = '0.660161815846869';
+set SomeApp['qux']['extra1'] = lexicaluuid();
+set SomeApp['qux']['extra2'] = lexicaluuid();
+set SomeApp['qux']['extra3'] = lexicaluuid();
+set SomeApp['qux']['extra4'] = lexicaluuid();
+set SomeApp['qux']['extra5'] = lexicaluuid();
+set SomeApp['qux']['extra6'] = lexicaluuid();
+set SomeApp['qux']['extra7'] = lexicaluuid();
http://git-wip-us.apache.org/repos/asf/cassandra/blob/e48b29a6/contrib/pig/test/test_storage.pig
----------------------------------------------------------------------
diff --git a/contrib/pig/test/test_storage.pig b/contrib/pig/test/test_storage.pig
new file mode 100644
index 0000000..22143dc
--- /dev/null
+++ b/contrib/pig/test/test_storage.pig
@@ -0,0 +1,22 @@
+rows = LOAD 'cassandra://PigTest/SomeApp' USING CassandraStorage();
+-- full copy
+STORE rows INTO 'cassandra://PigTest/CopyOfSomeApp' USING CassandraStorage();
+-- single tuple
+onecol = FOREACH rows GENERATE key, percent;
+STORE onecol INTO 'cassandra://PigTest/CopyOfSomeApp' USING CassandraStorage();
+-- bag only
+other = FOREACH rows GENERATE key, columns;
+STORE other INTO 'cassandra://PigTest/CopyOfSomeApp' USING CassandraStorage();
+
+
+-- filter
+likes = FILTER rows by vote_type.value eq 'like' and rating.value > 5;
+dislikes_extras = FILTER rows by vote_type.value eq 'dislike' AND COUNT(columns) > 0;
+
+-- store these too
+STORE likes INTO 'cassandra://PigTest/CopyOfSomeApp' USING CassandraStorage();
+STORE dislikes_extras INTO 'cassandra://PigTest/CopyOfSomeApp' USING CassandraStorage();
+
+-- filter to fully visible rows (no uuid columns) and dump
+visible = FILTER rows BY COUNT(columns) == 0;
+dump visible;