I may have missed something, but is there a way to use Cassanity to return the schema

Schema discovery about cassanity HOT 2 CLOSED

jnunemaker commented on September 8, 2024

Schema discovery

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Comments (2)

jnunemaker commented on September 8, 2024

There is nothing in cassanity currently. I think the reason is that when I initially wrote it, cass was changing the cql query for getting schema so I avoided it (column names and such).

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gavinheavyside commented on September 8, 2024

Thanks for replying. It shouldn't be too difficult to knock up something basic (experiments below). If I feel the need for it in Cassanity in future I'll open a PR.

# columns and types
> Hash[ sc.select(where: {keyspace_name: :keyspace, columnfamily_name: :colfam} ).
  map{|col| [col['column_name'], Cassanity::Column::Types[col['validator']]]} ]

{:where=>{:keyspace_name=>:keyspace, :columnfamily_name=>:colfam}, :column_family_name=>:schema_columns, :keyspace_name=>:system}
SELECT * FROM system.schema_columns WHERE "keyspace_name" = ? AND "columnfamily_name" = ?
keyspace
colfam

=> {"col1"=>:text,
 "col2"=>:float,
 "col3"=>:float,
 "col4"=>:timeuuid,
 "col5"=>:float}

# partition key (order by component index to handle compound keys)
# also try col['type'] == 'clustering_column'
> sc.select(where: {keyspace_name: :keyspace, columnfamily_name: :colfam} ).
  select{|col| col['type'] == 'partition_key' }.
  sort_by{|col| col['component_index']}.
  map{|col| col['column_name']}

{:where=>{:keyspace_name=>:keyspace, :columnfamily_name=>:colfam}, :column_family_name=>:schema_columns, :keyspace_name=>:system}
SELECT * FROM system.schema_columns WHERE "keyspace_name" = ? AND "columnfamily_name" = ?
keyspace
colfam

=> ["col1"]