Remote Column CRUD

In addition to row data synchronization, a remote table can synchronize column definitions with the server.

This enables:

• Dynamic column creation

• Column property updates

• Column removal

• Centralized schema management

Column operations require corresponding remote endpoints.

Enabling Remote Column Management

To manage columns remotely, configure:

• getColumns

• addColumn

• updateColumn

• removeColumn

Example:

const orders = dataManager.addTable("orders", {
    remote: {
        read: {
            url: "http://localhost:3000/api/orders",
            method: "GET"
        },
        getColumns: {
            url: "http://localhost:3000/api/orders/columns",
            method: "GET"
        },
        addColumn: {
            url: "http://localhost:3000/api/orders/columns",
            method: "POST"
        },
        updateColumn: {
            url: "http://localhost:3000/api/orders/columns",
            method: "PUT"
        },
        removeColumn: {
            url: "http://localhost:3000/api/orders/columns",
            method: "DELETE"
        }
    },
    autoSync: true
});

orders.fetch();

getColumns

getColumns retrieves the column definitions from the server.

Typical use:

• Initialize schema from remote storage

• Ensure client and server column structures match

The response should return a column definition list compatible with DataManager.

Column structure details are described in the API reference.

addColumn

When a new column is defined in the TableSheet, a remote request is sent.

In single sync mode:

• The request is sent immediately.

• The server persists the new column definition.

In batch mode:

• The change is stored locally.

• The column change is sent during submitChanges().

updateColumn

When column properties are modified:

• Caption

• Data type

• Default value

• Primary key flag

The corresponding remote endpoint is invoked.

In single sync mode:

• Sent immediately.

In batch mode:

• Stored and submitted together with other changes.

removeColumn

When a column is removed:

• The server must delete the corresponding column definition.

• Associated data behavior depends on server implementation.

In single sync mode:

• Immediate request.

In batch mode:

• Included in the batch payload.

Batch Behavior for Column Changes

If batch: true is enabled:

• Row changes and column changes are combined.

• submitChanges() sends all modifications together.

• The server should treat the batch as atomic if possible.

Example submission flow:

orders.submitChanges();

To cancel pending changes:

orders.cancelChanges();

Batch payload may include:

• addColumn

• updateColumn

• removeColumn

• insert

• update

• delete

Exact request structure is defined in the API reference.

Custom Column Handlers

Instead of URL configurations, operations can be defined as functions:

const orders = dataManager.addTable("orders", {
    remote: {
        read: function () {
            return Promise.resolve([...]);
        },
        addColumn: function (change) {
            return Promise.resolve(change);
        }
    },
    autoSync: true
});

This allows:

• Custom transport logic

• Middleware integration

• Mock implementations

Important Constraints

Remote column synchronization requires:

• Consistent column identifiers (value)

• Server-side support for column persistence

• Proper handling of data-type changes

If server validation fails:

• The operation should return an error

• The table state will reflect the failure

Server-side schema enforcement is application-specific.