getColumnsV2.md

getColumns: Gets the column descriptions

This command gets the specified columns descriptions in the database.

Result set columns: Ordered by SCHEMA, TABLE, ORDINAL_POSITION.

Name	Data Type	Description
SCHEMA	string	schema name
TABLE	string	table name
NAME	string	column name
TABLE_TYPE	string	table type (supported values are "SYSTEM TABLE", "TABLE", "VIEW")
TYPE	string	data type
TYPE_ID	number	data type ID
MAXSIZE	number	maximum number of characters for strings
NUM_PREC	number	precision for numeric values
NUM_SCALE	number	scale for numeric values
ORDINAL_POSITION	number	column position in the table (beginning with 1)
IS_VIRTUAL	boolean	is part of a virtual table
IS_NULLABLE	boolean	are NULL values allowed (value is NULL for views)
IS_DISTRIBUTION_KEY	boolean	column is part of the distribution key
PARTITION_KEY_ORDINAL_POSITION	number	column position (beginning with 1) in the table's composite partition key, NULL for columns which are not part of it
DEFAULT	string	default value
IS_IDENTITY	boolean	has the identity attribute
OWNER	string	owner name
COMMENT	string	column comment

If the command returns a result set which has less than 1,000 rows of data, the data will be provided in the data field of resultSet. However if the command returns a result set which has 1,000 or more rows of data, a result set will be opened whose handle is returned in the resultSetHandle field of resultSet. Using this handle, the data from the result set can be retrieved using the fetch command. Once the result set is no longer needed, it should be closed using the closeResultSet command.

Request fields:

• command (string) => command name: "getColumns"
• attributes (object, optional) => attributes to set for the connection (see Attributes)
• schema (string, optional) => schema name search criteria in SQL LIKE format. "" means no schema, null means all schemas.
• table (string, optional) => table name search criteria in SQL LIKE format. "" means no table, null means all tables.
• column (string, optional) => column name search criteria in SQL LIKE format. "" means no column, null means all columns.
• tableTypes (string[], optional) => array of table types (supported values are "SYSTEM TABLE", "TABLE", "VIEW"). null means all table types.

Request JSON format

 {
     "command": "getColumns",
     "attributes": {
             // as defined separately
     },
     "schema": <string>,
     "table": <string>,
     "column": <string>,
     "tableTypes": [
                  <string>
     ]
 }

Response fields:

• status (string) => command status: "ok" or "error"
• attributes (object, optional) => attributes set for the connection (see Attributes)
• responseData (object, optional) => only present if status is "ok"
  • numResults (number) => number of result objects
  • results (object[]) => array of result objects
    • resultType (string) => type of result: "resultSet"
    • resultSet (object) => result set
      • resultSetHandle (number, optional) => result set handle
      • numColumns (number) => number of columns in the result set
      • numRows (number) => number of rows in the result set
      • numRowsInMessage (number) => number of rows in the current message
      • columns (object[]) => array of column metadata objects
        • name (string) => column name
        • dataType (object) => column metadata
          • type (string) => column data type
          • precision (number, optional) => column precision
          • scale (number, optional) => column scale
          • size (number, optional) => maximum size in bytes of a column value
          • characterSet (string, optional) => character encoding of a text column
      • data (array[], optional) => object containing the data in column-major order
• exception (object, optional) => only present if status is "error"
  • text (string) => exception message which provides error details
  • sqlCode (string) => five-character exception code if known, otherwise "00000"

Response JSON format

 {
     "status": <"ok" | "error">,
     "attributes": {
         // as defined separately
     },
     // in case of "ok"
     "responseData": {
         "numResults": <number>,
         "results": [ {
             "resultType": "resultSet",
             "resultSet": {
                 "resultSetHandle": <number>,
                 "numColumns": <number>,
                 "numRows": <number>,
                 "numRowsInMessage": <number>,
                 "columns": [ {
                     "name": <string>,
                     "dataType": {
                         "type": <string>,
                         "precision": <number>,
                         "scale": <number>,
                         "size": <number>,
                         "characterSet": <string>
                     }
                 } ],
                 "data": [
                     [
                         <string | number | true | false | null>
                     ]
                 ]
             }
         } ]
     },
     // in case of "error"
     "exception": {
         "text": <string>,
         "sqlCode": <string>
     }
 }