Table Format Options

Pluggable table format rendering system that allows PostgreSQL function results to be rendered as HTML tables or Excel spreadsheet downloads instead of JSON, controlled by the @table_format annotation.

Applies to Set-Returning Functions Only

Table format rendering only applies to routines that return SETOF or TABLE results. Scalar-returning functions are not affected.

Overview

json

{
  "NpgsqlRest": {
    "TableFormatOptions": {
      "Enabled": false,
      "HtmlEnabled": true,
      "HtmlKey": "html",
      "HtmlHeader": "<style>table{font-family:Calibri,Arial,sans-serif;font-size:11pt;border-collapse:collapse}th,td{border:1px solid #d4d4d4;padding:4px 8px}th{background-color:#f5f5f5;font-weight:600}</style>",
      "HtmlFooter": null,
      "ExcelEnabled": true,
      "ExcelKey": "excel",
      "ExcelSheetName": null,
      "ExcelDateTimeFormat": null,
      "ExcelNumericFormat": null
    }
  }
}

General Settings

Setting	Type	Default	Description
Enabled	bool	false	Enable table format handlers. When false, @table_format annotations are ignored.

HTML Table Handler

Renders results as a styled HTML table suitable for browser viewing and copy-paste into Excel. Activated by the @table_format = html annotation on PostgreSQL functions returning SETOF or TABLE.

json

{
  "NpgsqlRest": {
    "TableFormatOptions": {
      "Enabled": true,
      "HtmlEnabled": true,
      "HtmlKey": "html",
      "HtmlHeader": "<style>table{font-family:Calibri,Arial,sans-serif;font-size:11pt;border-collapse:collapse}th,td{border:1px solid #d4d4d4;padding:4px 8px}th{background-color:#f5f5f5;font-weight:600}</style>",
      "HtmlFooter": null
    }
  }
}

Setting	Type	Default	Description
HtmlEnabled	bool	true	Enable the HTML table handler.
HtmlKey	string	"html"	The key name used to match @table_format = <key> annotation.
HtmlHeader	string	(CSS style block)	Content written before the HTML table. Typically a CSS style block. Set to null to omit.
HtmlFooter	string	null	Content written after the closing HTML table tag. Set to null to omit.

Example

sql

create function get_report()
returns table (id int, name text, amount numeric)
language sql as $$
  select * from reports;
$$;

comment on function get_report() is '
HTTP GET
@table_format = html
';

This renders the function result as an HTML table instead of JSON.

Excel Table Handler

Renders results as an .xlsx Excel spreadsheet download using the SpreadCheetah library (streaming, AOT-compatible). Activated by the @table_format = excel annotation on PostgreSQL functions returning SETOF or TABLE.

json

{
  "NpgsqlRest": {
    "TableFormatOptions": {
      "Enabled": true,
      "ExcelEnabled": true,
      "ExcelKey": "excel",
      "ExcelSheetName": null,
      "ExcelDateTimeFormat": null,
      "ExcelNumericFormat": null
    }
  }
}

Setting	Type	Default	Description
ExcelEnabled	bool	true	Enable the Excel handler.
ExcelKey	string	"excel"	The key name used to match @table_format = <key> annotation.
ExcelSheetName	string	null	Worksheet name. When null, uses the routine name.
ExcelDateTimeFormat	string	null	Excel Format Code for DateTime cells. When null, uses SpreadCheetah default (yyyy-MM-dd HH:mm:ss). Uses Excel Format Codes (not .NET format strings). Examples: yyyy-mm-dd, dd/mm/yyyy hh:mm, m/d/yy h:mm.
ExcelNumericFormat	string	null	Excel Format Code for numeric cells. When null, uses Excel default (General). Uses Excel Format Codes (not .NET format strings). Examples: #,##0.00, 0.00, #,##0.

Example

sql

create function get_report()
returns table (id int, name text, amount numeric)
language sql as $$
  select * from reports;
$$;

comment on function get_report() is '
HTTP GET
@table_format = excel
';

This returns an .xlsx file download instead of JSON.

Per-Endpoint Overrides

The download filename and worksheet name can be overridden per-endpoint via custom parameter annotations:

sql

comment on function get_report() is '
HTTP GET
@table_format = excel
@excel_file_name = monthly_report.xlsx
@excel_sheet = Report Data
';

These also support dynamic placeholders resolved from function parameters:

sql

create function get_report(_format text, _file_name text, _sheet_name text)
returns table (id int, name text, amount numeric)
language sql as $$
  select * from reports;
$$;

comment on function get_report(text, text, text) is '
HTTP GET
@table_format = {_format}
@excel_file_name = {_file_name}
@excel_sheet = {_sheet_name}
';

Complete Example

Production configuration with both HTML and Excel handlers:

json

{
  "NpgsqlRest": {
    "TableFormatOptions": {
      "Enabled": true,
      "HtmlEnabled": true,
      "HtmlKey": "html",
      "HtmlHeader": "<style>table{font-family:Calibri,Arial,sans-serif;font-size:11pt;border-collapse:collapse}th,td{border:1px solid #d4d4d4;padding:4px 8px}th{background-color:#f5f5f5;font-weight:600}</style>",
      "HtmlFooter": null,
      "ExcelEnabled": true,
      "ExcelKey": "excel",
      "ExcelSheetName": null,
      "ExcelDateTimeFormat": "yyyy-mm-dd",
      "ExcelNumericFormat": "#,##0.00"
    }
  }
}

Related

• Custom Parameters annotation - Set table_format, excel_file_name, and excel_sheet per-endpoint
• Code Generation - TypeScript client code generation with tsclient_export_url and tsclient_url_only
• Comment Annotations Guide - How annotations work
• Configuration Guide - How configuration works

Next Steps

• Upload Options - Configure file upload handlers
• NpgsqlRest Options - Configure general NpgsqlRest settings