Hi all! We have encountered the following problem. We create our column families via hector like this:
ColumnFamilyDefinition cfdef = HFactory.createColumnFamilyDefinition(* "mykeyspace"*, *"mycf"*); cfdef.setColumnType(ColumnType.*STANDARD*); cfdef.setComparatorType(ComparatorType.*UTF8TYPE*); cfdef.setDefaultValidationClass(*"BytesType"*); cfdef.setKeyValidationClass(*"UTF8Type"*); cfdef.setReadRepairChance(0.1); cfdef.setGcGraceSeconds(864000); cfdef.setMinCompactionThreshold(4); cfdef.setMaxCompactionThreshold(32); cfdef.setReplicateOnWrite(*true*); cfdef.setCompactionStrategy(*"SizeTieredCompactionStrategy"*); Map<String, String> compressionOptions = *new* HashMap<String, String>(); compressionOptions.put(*"sstable_compression"*, *""*); cfdef.setCompressionOptions(compressionOptions); cluster.addColumnFamily(cfdef, *true*); When we *describe *this column family via *cqlsh* we get this CREATE TABLE "mycf" ( key text, column1 text, value blob, PRIMARY KEY (key, column1) ) WITH COMPACT STORAGE AND bloom_filter_fp_chance=0.010000 AND caching='KEYS_ONLY' AND comment='' AND dclocal_read_repair_chance=0.000000 AND gc_grace_seconds=864000 AND read_repair_chance=0.100000 AND replicate_on_write='true' AND populate_io_cache_on_flush='false' AND compaction={'class': 'SizeTieredCompactionStrategy'} AND compression={}; As you can see there is a mysterious *column1* and moreover it is added to the primary key. We've thought it wrong so we've tried getting rid of it. We've managed to do it by adding explicit column definitions like this: BasicColumnDefinition cdef = new BasicColumnDefinition(); cdef.setName(StringSerializer.get().toByteBuffer(*"mycolumn"*)); cdef.setValidationClass(ComparatorType.*BYTESTYPE*.getTypeName()); cdef.setIndexType(ColumnIndexType.*CUSTOM*); cfdef.addColumnDefinition(cDef); After this the primary key was like PRIMARY KEY (key) The effect of this was *overwhelming* - we got a tremendous performance improvement and according to stats, the key cache began working while previously its hit ratio was close to zero. My questions are 1) What is this all about? Is what we did right? 2) In this project we can provide explicit column definitions. But in another project we have some column families where this is not possible because column names are dynamic (based on timestamps). If what we did is right - how can we adapt this solution to the dynamic column name case?