Querying tables

Read table rows as JSON with column selection, filtering, sorting and offset pagination — documented against the live API.

Read rows from a table as JSON with the query endpoint. The query is sent as a JSON request body:

POST/namespaces/{namespace}/tables/{tableName}/query

It returns the rows plus offset pagination metadata:

{ "data": [ /* rows */ ], "total": 22143, "total_pages": 4429, "current_page": 1 }

Request body

Send a JSON object. Every field is optional — an empty body {} returns the first page of all columns.

Parameter	Type	Description
`select`	string	Comma-separated column names to return. Omit for all columns.
`filter`	string	Filter expression: column=value conditions with optional operators and _and/_or (see below).
`sort`	string	Comma-separated sort keys. Prefix - for descending, + or none for ascending.
`limit`	int	Maximum rows to return (page size).
`offset`= 0	int	Rows to skip — offset = (page − 1) × limit.
`exclude_nulls`	string[]	Column name(s) that must be non-null; rows with a null there are dropped.

Select columns

select is a comma-separated projection. Omit it to get every column.

curl -X POST 'https://api.dataportal.gov.lt/namespaces/111958286/tables/mirusiuju_toksikologinis_rezultatas/query' \
  -H 'Content-Type: application/json' \
  -d '{"select":"lytis,mirties_metai,pavadinimas","limit":3}'

filter is a URL-style expression carried in the body as a string: column=value conditions joined with &, optionally using comparison operators and _and / _or groups. Values are written bare — no quotes needed, even for text with spaces.

# Equality — female decedents (5 243 rows)
curl -X POST 'https://api.dataportal.gov.lt/namespaces/111958286/tables/mirusiuju_toksikologinis_rezultatas/query' \
  -H 'Content-Type: application/json' \
  -d '{"filter":"lytis=Moteris","limit":1}'

Operators

Append a dotted, two-letter operator to the column. Omit it for equality.

Parameter	Type	Description
`col=v`	equals	Exact match (e.g. lytis=Moteris).
`col._gt=v`	greater than	e.g. mirties_metai._gt=2020
`col._ge=v`	≥	greater than or equal
`col._lt=v`	less than
`col._le=v`	≤	less than or equal
`col._co=v`	contains	substring match (e.g. pavadinimas._co=Etan)
`col._sw=v`	starts with
`col._ew=v`	ends with

# Substance name containing "Etan" (13 345 rows)
curl -X POST 'https://api.dataportal.gov.lt/namespaces/111958286/tables/mirusiuju_toksikologinis_rezultatas/query' \
  -H 'Content-Type: application/json' \
  -d '{"filter":"pavadinimas._co=Etan","limit":1}'

Use the two-letter operators

The operator names are two letters: ._ge / ._le, not ._gte / ._lte. The three-letter forms are rejected by the query engine (they come back as a 502). (Some spec examples show ._gte — that is a spec bug.)

Combining conditions — `_and` / `_or`

Join conditions inside the filter string with &. Each extra condition is _and by default; prefix it with _or. for a disjunction. The operator (or none, for equality) still dots onto the column.

# 2018+ AND female (4 570 rows)
curl -X POST 'https://api.dataportal.gov.lt/namespaces/111958286/tables/mirusiuju_toksikologinis_rezultatas/query' \
  -H 'Content-Type: application/json' \
  -d '{"filter":"mirties_metai._ge=2018&_and.lytis=Moteris","limit":1}'

# female OR male
curl -X POST 'https://api.dataportal.gov.lt/namespaces/111958286/tables/mirusiuju_toksikologinis_rezultatas/query' \
  -H 'Content-Type: application/json' \
  -d '{"filter":"lytis=Moteris&_or.lytis=Vyras","limit":1}'

The response total reflects the filtered set, so it's the quickest way to check a filter is doing what you expect.

Sort

sort takes comma-separated column names. Prefix - for descending, + (or nothing) for ascending.

# Newest deaths first
curl -X POST 'https://api.dataportal.gov.lt/namespaces/111958286/tables/mirusiuju_toksikologinis_rezultatas/query' \
  -H 'Content-Type: application/json' \
  -d '{"sort":"-mirties_metai","limit":5}'

Pagination

Pagination is offset-based and maps straight to SQL LIMIT / OFFSET:

limit — page size
offset — rows to skip; offset = (page − 1) × limit

The response reports total (all matching rows), total_pages (for the current limit), and current_page.

First page

curl -X POST '…/query' -H 'Content-Type: application/json' -d '{"limit":100,"offset":0}'

Add limit to the offset each time — page 2 is offset=100, page 3 offset=200, …

curl -X POST '…/query' -H 'Content-Type: application/json' -d '{"limit":100,"offset":100}'

Stop

When current_page reaches total_pages (or fewer than limit rows come back), you're done.

Walk every page

A copy-paste loop that pages through the whole table until the last (short) page:

URL='https://api.dataportal.gov.lt/namespaces/111958286/tables/mirusiuju_toksikologinis_rezultatas/query'
LIMIT=1000
OFFSET=0
while :; do
  RESP=$(curl -s -X POST "$URL" -H 'Content-Type: application/json' \
    -d "{\"limit\":$LIMIT,\"offset\":$OFFSET,\"sort\":\"_id\"}")
  COUNT=$(echo "$RESP" | jq '.data | length')
  echo "offset=$OFFSET  got=$COUNT  total=$(echo "$RESP" | jq '.total')"
  [ "$COUNT" -lt "$LIMIT" ] && break   # last page: fewer than limit rows
  OFFSET=$((OFFSET + LIMIT))
done

import requests

URL = "https://api.dataportal.gov.lt/namespaces/111958286/tables/mirusiuju_toksikologinis_rezultatas/query"
limit, offset = 1000, 0
while True:
    resp = requests.post(URL, json={"limit": limit, "offset": offset, "sort": "_id"}).json()
    rows = resp["data"]
    print(f"offset={offset} got={len(rows)} total={resp['total']}")
    if len(rows) < limit:
        break  # last page
    offset += limit

const URL = "https://api.dataportal.gov.lt/namespaces/111958286/tables/mirusiuju_toksikologinis_rezultatas/query";
const limit = 1000;
let offset = 0;
while (true) {
  const resp = await (await fetch(URL, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ limit, offset, sort: "_id" }),
  })).json();
  console.log(`offset=${offset} got=${resp.data.length} total=${resp.total}`);
  if (resp.data.length < limit) break; // last page
  offset += limit;
}

Two things that bite

Always add a stable sort (e.g. sort=_id). Without a fixed order the query engine may return rows differently between requests, so offset paging can skip or repeat rows. A filter shrinks total, so you page the filtered set.
Deep offsets get slow — OFFSET still scans the rows it skips. To pull the whole table, don't paginate at all: use the export endpoint, which streams the entire result set in one request.

Drop null rows

exclude_nulls names one or more columns that must be non-null; rows with a null in any of them are dropped from the result. Pass it as a JSON array:

curl -X POST '…/query' -H 'Content-Type: application/json' \
  -d '{"exclude_nulls":["m_konc","pavadinimas"],"limit":5}'

Try it

Build a query against the live table and run it:

POST/namespaces/111958286/tables/mirusiuju_toksikologinis_rezultatas/query

Columns (select)

limitoffset

Sort

Filter

value

curl -X POST 'https://api.dataportal.gov.lt/namespaces/111958286/tables/mirusiuju_toksikologinis_rezultatas/query' \
  -H 'Content-Type: application/json' \
  -d '{"limit":10,"select":"pavadinimas,lytis,mirties_metai,gyv_tipas","sort":"mirties_metai","filter":"lytis=Moteris"}'

1 rows shown · total: 5 243 · page 1

Response

lytis	mirties_metai	pavadinimas	gyv_tipas
Moteris	2021	Etanolis (etilo alkoholis)	Kaimas

Downloading data

When you want the whole result set as a file.

Errors

What 400 / 404 / 502 responses look like.

Request body

Select columns

Filter

Operators

Combining conditions — `_and` / `_or`

Sort

First page

Next page

Stop

Walk every page

Drop null rows

Try it

Downloading data

Errors

See also

On this page