Fields, Ordering & Pagination

Control which fields are returned, how results are sorted, and how to paginate.

Field Selection

Control which fields are returned using fields:

Array Format (Recommended)

await repo.find({
  filter: {
    where: { status: 'active' },
    fields: ['id', 'email', 'name']
  }
});
// Returns only: { id, email, name }

Object Format

// Include specific fields
await repo.find({
  filter: {
    fields: { id: true, email: true, name: true }
  }
});

// Exclude specific fields
await repo.find({
  filter: {
    fields: { password: false, secret: false }
  }
});

Ordering

Basic Ordering

// Single column, descending
await repo.find({
  filter: { order: ['createdAt DESC'] }
});

// Multiple columns
await repo.find({
  filter: { order: ['status ASC', 'createdAt DESC'] }
});

// Default direction is ASC
await repo.find({
  filter: { order: ['name'] }  // Same as 'name ASC'
});

JSON Path Ordering

Order by nested fields in JSON columns:

await repo.find({
  filter: { order: ['metadata.priority DESC'] }
});
// SQL: ORDER BY "metadata" #> '{priority}' DESC

await repo.find({
  filter: { order: ['settings.display.theme ASC'] }
});

JSONB Sort Order

JSONB Type	Sort Order
null	First (lowest)
boolean	false < true
number	Numeric order
string	Lexicographic
array	Element-wise
object	Key-value

Pagination

Limit and Skip

// First 10 results
await repo.find({
  filter: { limit: 10 }
});

// Page 2 (skip first 10, get next 10)
await repo.find({
  filter: { limit: 10, skip: 10 }
});

// Page N formula: skip = (page - 1) * limit
const page = 3;
const pageSize = 20;
await repo.find({
  filter: {
    limit: pageSize,
    skip: (page - 1) * pageSize
  }
});

TIP

Always use limit for public-facing endpoints to prevent memory exhaustion.

Pagination Helper

function getPaginationFilter(page: number, pageSize: number = 20) {
  return {
    limit: pageSize,
    skip: (page - 1) * pageSize
  };
}

// Usage
const filter = {
  where: { status: 'active' },
  ...getPaginationFilter(3, 20)
};
// { where: {...}, limit: 20, skip: 40 }

Range Queries (Content-Range Header)

When building paginated APIs, you often need to return the total count alongside the data for pagination UI. Use shouldQueryRange: true to get range information following the HTTP Content-Range standard.

Basic Usage

const result = await repo.find({
  filter: { limit: 10, skip: 20 },
  options: { shouldQueryRange: true }
});

// Result structure:
// {
//   data: [...],  // Array of records
//   range: {
//     start: 20,   // Starting index (inclusive)
//     end: 29,     // Ending index (inclusive)
//     total: 100   // Total matching records
//   }
// }

Setting HTTP Headers

Use the range information to set standard HTTP headers:

const { data, range } = await repo.find({
  filter: { limit: 10, skip: 20, where: { status: 'active' } },
  options: { shouldQueryRange: true }
});

// Format: "records start-end/total"
const contentRange = data.length > 0
  ? `records ${range.start}-${range.end}/${range.total}`
  : `records */${range.total}`;

res.setHeader('Content-Range', contentRange);
// → "records 20-29/100"

TDataRange Type

type TDataRange = {
  start: number;  // Starting index (0-based, inclusive)
  end: number;    // Ending index (0-based, inclusive)
  total: number;  // Total count matching the query
};

Content-Range Format Reference

Scenario	Content-Range Header
Items 0-9 of 100	records 0-9/100
Items 20-29 of 100	records 20-29/100
No items found	records */0
Last page (items 90-99)	records 90-99/100

Performance Note

When shouldQueryRange: true, the repository executes the data query and count query in parallel using Promise.all for optimal performance.

Combined Example

await repo.find({
  filter: {
    where: { status: 'active' },
    fields: ['id', 'name', 'price', 'createdAt'],
    order: ['price ASC', 'createdAt DESC'],
    limit: 20,
    skip: 0
  }
});

With Range Information

const { data, range } = await repo.find({
  filter: {
    where: { status: 'active' },
    fields: ['id', 'name', 'price', 'createdAt'],
    order: ['price ASC', 'createdAt DESC'],
    limit: 20,
    skip: 0
  },
  options: { shouldQueryRange: true }
});

console.log(`Showing ${range.start}-${range.end} of ${range.total}`);
// → "Showing 0-19 of 150"