Example 1

Example of conf.json and resulting summary.

{
  "db": "postgresql://postgres:postgres@localhost:5432/trydatasets",
  "github.com":{
    "lexml/lexml-vocabulary":null,
    "datasets/language-codes":null,
    "datasets/country-codes":null,
    "datasets/world-cities":{
      "_corrections_":{"resources":[{"primaryKey": "geonameid"}]}
    },
    "datasets-br/state-codes":"br-state-codes",
    "datasets-br/city-codes":null
  },
  "useBig":true,  "useIDX":false,        "useRename":true,
  "useYUml":true, "useAllNsAsDft":false
}

After run all as showed by How to install, you get at terminal two tables of summarizations:

id	(ns) urn	pkey	jtd	n_cols	n_rows
1	(2)lexml:autoridade	id	tab-aoa	9	601
4	(2)lexml:evento	id	tab-aoa	9	14
5	(2)lexml:lingua	id	tab-aoa	9	6
2	(2)lexml:localidade	id	tab-aoa	9	5664
6	(2)lexml:tipoconteudo	id	tab-aoa	9	6
3	(2)lexml:tipodocumento	id	tab-aoa	9	2372
11	(3)datasets:country_codes		tab-aoa	56	250
10	(3)datasets:ietf_language_tags		tab-aoa	7	721
7	(3)datasets:language_codes		tab-aoa	2	184
8	(3)datasets:language_codes_3b2		tab-aoa	3	184
9	(3)datasets:language_codes_full		tab-aoa	5	486
12	(3)datasets:world_cities	geonameid	tab-aoa	4	23018
15	(4)datasets-br:br_city_codes	state/lexLabel	tab-aoa	9	5570
14	(4)datasets-br:br_city_synonyms	state/lexLabel/synonym	tab-aoa	5	26
13	(4)datasets-br:br_state_codes	id	tab-aoa	15	33

This 15 rows-summary was obtained by select * from dataset.vmeta_summary. The first column is the source-id, id at dataset.meta table. The (ns) is the namespace-ID, used to labeling the SQL-VIEWs, to avoid long names, so for the first the view name is dataset.vw2_autoridade. When dataset is in the "empty namespace" (default or forced when using "all namespaces as default" flag, useAllNsAsDft) the view name will be dataset.vw_autoridade.

URN is only a short to "nameSpace:datasetName", using a string with some URN conventions. Next coluns in the summary are pkey for the primary-keys when exists, and jtd for JSON Type Definition used in the dataset.big.j internal structure; cols show the "number of coluns" (fields) and rows the number of lines of data.

nspname	n_tables	total_bytes	table_bytes	table_size
dataset	4	1474560	73728	72 kB

This other summary is only for check disk-usage, it is generated by select * from pgvw_nsclass_usage where nspname='dataset'. You can use similar one to check only the dataset.big table,