Data Process.


It creates a new datacube with random data and dimensions.


  • container: name of an existing container.
  • cwd: absolute path corresponding to the current working directory, used to select the folder where the container is located.
  • host_partition: name of I/O host partition used to store data; by default the first available host partition will be used.
  • ioserver: type of I/O server used to store data. Possible values are: “mysql_table” (default) or “ophidiaio_memory”.
  • schedule: scheduling algorithm. The only possible value is 0, for a static linear block distribution of resources.
  • nhost: number of output hosts. With default value (‘0’), all host available in the host partition are used.
  • nfrag: number of fragments per database.
  • ntuple: number of tuples per fragment.
  • run: if set to ‘no’, the operator simulates the creation and computes the fragmentation parameters that would be used else, if set to ‘yes’, the actual cube creation is executed.
  • measure: name of the measure used in the datacube.
  • measure_type: type of measures. Possible values are “double”, “float” or “int”.
  • exp_ndim: used to specify how many dimensions in dim argument, starting from the first one, must be considered as explicit dimensions. NOTE: the new datacube must have at least one implicit dimension, hence the total number of dimensions is bigger or equal than exp_ndim +1.
  • dim: name of the dimension. Multiple-value field: list of dimensions separated by “|” can be provided.
  • concept_level: concept level short name (must be a single char). Default value is “c”. Multiple-value field: list of concept levels separated by “|” can be provided.
  • dim_size: size of random dimension. Multiple-value field: list of dimension sizes separated by “|” can be provided.
  • compressed: if set to “yes”, new data will be compressed. With “no” (default), data will be inserted without compression.
  • grid: optional argument used to identify the grid of dimensions to be used (if the grid already exists) or the one to be created (if the grid has a new name). If it isn’t specified, no grid will be used.
  • description: additional description to be associated with the output cube.
  • algorithm: it can be used to specify the type of emulation schema used to generate data. By default values are sampled indipendently from a uniform distribution in the range [0, 1000]. If “temperatures” is used, then values are generated with a first order auto-regressive model to be consistent with temperature values (in Celsius).

System parameters

  • exec_mode: operator execution mode. Possible values are async (default) for asynchronous mode, sync for synchronous mode with json-compliant output.
  • ncores: number of parallel processes to be used (min. 1).
  • sessionid: session identifier used server-side to manage sessions and jobs. Usually, users don’t need to use/modify it, except when it is necessary to create a new session or switch to another one.
  • objkey_filter: filter on the output of the operator written to file (default=all => no filter, none => no output, randcube => shows operator’s output PID as text in case “run” is “yes”, else the parameter check is shown).


Generate a random compressed data cube with 1 host, 16 fragments/db, 10 tuples/fragment, 10 elements/tuple, with ‘pressure’ measure and ‘lat’, ‘lon’ and ‘time’ dimensions, in the container ‘container1’:

[OPH_TERM] >>  oph_randcube container=container1;nhost=1;nfrag=16;ntuple=10;measure=Pressure;measure_type=double;exp_ndim=2;dim=lat|lon|time;concept_level=c|c|d;dim_size=16|10|10;compressed=yes;


Argument name Type Mandatory Values Default Min/Max-value
sessionid “string” “no”   “null”  
ncores “int” “no”   “1” “1” /
exec_mode “string” “no” “async|sync” “async”  
container “string” “yes”      
cwd “string” “yes”      
host_partition “string” “no”   “auto”  
ioserver “string” “no” “mysql_table|ophidiaio_memory” “mysql_table”  
schedule “int” “no” “0” “0”  
nhost “int” “no”   “0” “0” /
run “string” “no” “yes|no” “yes”  
nfrag “int” “yes”     “1” /
ntuple “int” “yes”     “1” /
measure “string” “yes”      
measure_type “string” “yes” “double|float|int|long|short|byte”    
exp_ndim “int” “yes”     “1” /
dim “string” “yes”      
concept_level “string” “no”   “c”  
dim_size “string” “yes”      
compressed “string” “no” “yes|no” “no”  
grid “string” “no”   “-“  
description “string” “no”   “-“  
objkey_filter “string” “no” “all|none|randcube” “all”  
algorithm “string” “no” “default|temperatures” “default”