Returns sample rows from a table (optionally only some columns, with a filter) or from a SQL query. Row access and Table & column access rules apply unless all=true.

Method and path	POST /plugin/datafor-modeler/api/metadata/previewcolumn
Permission	Read on the connection. A where or a column expression needs permission to use SQL fragments on the connection; sql needs permission to run raw SQL; all=true needs Full control.
Content type	application/x-www-form-urlencoded

POST /plugin/datafor-modeler/api/metadata/preview takes the same parameters and returns the same result.

Parameters

Name	In	Type	Required	Description
connection	form	string	Yes	Connection name.
schema	form	string	With table	Schema of the table.
table	form	string	table or sql	Table or view name.
sql	form	string	table or sql	A query to preview instead of a table. Takes precedence over table.
columns	form	string	No	Table only. JSON array of columns: {"name": "region"}, or {"name": "year", "detail": "extract(year from order_date)"} for an expression. Default: all columns the caller may see.
where	form	string	No	Filter condition, without the WHERE keyword.
start	form	integer	No	Default 0. Rows to skip.
limit	form	integer	No	Default 50. Capped at the server's maximum preview rows (default 1,000).
isEncode	form	boolean	No	Default false. true when sql, where, and each detail are Base64-encoded (UTF-8).
withParams	form	string	No	Default 0. 1 fills in global parameters used in the SQL with their default values when they are not in params.
params	form	string	No	JSON array of parameter values: {"name": "...", "value": "..."}.
isMoreDetail	form	boolean	No	Default false. Add formatting details to meta.
all	form	boolean	No	Default false. true skips Row access and Table & column access rules.

Example

curl -u admin:password -X POST \
  "http://localhost:28080/datafor/plugin/datafor-modeler/api/metadata/previewcolumn" \
  --data-urlencode "connection=Sales DW" \
  --data-urlencode "schema=public" \
  --data-urlencode "table=orders" \
  --data-urlencode 'columns=[{"name":"order_id"},{"name":"region"}]' \
  --data-urlencode "limit=2"

{
  "success": true,
  "msg": "success",
  "meta": [
    { "name": "order_id", "typeDesc": "Integer", "type": 5, "originalColumnTypeName": "int4" },
    { "name": "region", "typeDesc": "String", "type": 2, "originalColumnTypeName": "varchar", "length": 30 }
  ],
  "data": [
    { "order_id": 1001, "region": "North" },
    { "order_id": 1002, "region": "West" }
  ]
}

Errors

HTTP 200 with success: false.

code / msg	When
msg: parameter table or sql cannot be both empty	Neither table nor sql was sent.
code "403", msg: SQL_EXECUTE_FORBIDDEN:<connection>	sql was sent by a caller who may not run raw SQL on this connection.
code "403", msg: SQL_FRAGMENT_FORBIDDEN:<connection>	where or a column expression was sent by a caller who may not use SQL fragments on this connection.
code "401", msg: no table privileges / no column privileges	Table & column access hides the table or a requested column.
code "401", msg: No admin privileges:<connection>	all=true without Full control.
code "404", msg: table not found	The table does not exist.
code "400", msg: column not found:<name>	A requested column does not exist, or the condition is not allowed.

Related: Get connection sensitivity, Row-Level Security in Analytics