Alter a table
|
Tables with the Data API are currently in public preview. Development is ongoing, and the features and functionality are subject to change. Hyper-Converged Database (HCD), and the use of such, is subject to the DataStax Preview Terms. |
Alters a table by doing one of the following:
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Adding one or more columns to a table
-
Dropping one or more columns from a table
You cannot change a column’s type. Instead, you must drop the column and add a new column.
After you add a column, you should index the column if you want to filter or sort on the column. All indexed column names must use snake case, not camel case. For more information, see Create an index and Create a vector index.
|
Ready to write code? See the examples for this method to get started. If you are new to the Data API, check out the quickstart. |
Result
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Python
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TypeScript
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Java
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C#
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curl
Adds or drops columns.
Returns a Table instance that represents the table after the modification.
Although the Table instance that you used to perform the alteration will still work, it will not reflect the updated typing if you added or dropped columns.
To reflect the new typing, use the row_type parameter.
Adds or drops columns.
Returns a promise that resolves to a Table instance that represents the table after the modification.
Although the Table instance that you used to perform the alteration will still work, it will not reflect the updated typing if you added or dropped columns.
To reflect the new typing, provide the new type of the table to the alter method.
For example:
const newTable = await table.alter<NewSchema>({
operation: {
add: {
columns: {
venue: 'text',
},
},
},
});
Adds or drops columns.
Returns a Table<T> instance that represents the table after the schema change.
Although the Table instance that you used to perform the alteration will still work, it will not reflect the updated typing if you added or dropped columns.
To reflect the new typing, use the rowClass parameter.
Adds or drops columns.
Returns a Table instance that represents the table after the schema change.
Although the Table instance that you used to perform the alteration will still work, it will not reflect the updated typing.
To reflect the new typing, provide the new type of the table to the Alter or AlterAsync method.
Adds or drops columns.
If the command succeeds, the response indicates the success.
Example response:
{
"status": {
"ok": 1
}
}
Parameters
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Python
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TypeScript
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Java
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C#
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curl
Use the alter method, which belongs to the astrapy.Table class.
Method signature
alter(
operation: AlterTableOperation | dict[str, Any],
*,
row_type: type[Any] = DefaultRowType,
table_admin_timeout_ms: int,
request_timeout_ms: int,
timeout_ms: int,
) -> Table[NEW_ROW]
| Name | Type | Summary |
|---|---|---|
|
|
The alter operation to perform. Can be one of the following:
|
|
|
Optional.
A formal specifier for the type checker.
If provided, |
|
|
Optional.
A timeout, in milliseconds, for the underlying HTTP request.
If not provided, the |
Use the alter method, which belongs to the Table class.
Method signature
async alter(
options: AlterTableOptions<Schema>
): Table<Schema, PKey>
| Name | Type | Summary |
|---|---|---|
|
|
The alter operation to perform. Can be one of the following:
|
|
|
The timeout(s) to apply to HTTP request(s) originating from this method. |
Use the alter method, which belongs to the com.datastax.astra.client.tables.Table class.
Method signature
Table<T> alter(AlterTableOperation operation)
Table<T> alter(
AlterTableOperation operation,
AlterTableOptions options
)
<R> Table<R> alter(
AlterTableOperation operation,
AlterTableOptions options,
Class<R> clazz
)
| Name | Type | Summary |
|---|---|---|
|
|
The alter operation to perform. Can be one of the following:
|
|
Optional. The options for this operation, including the timeout. |
|
|
|
Optional. A specification of the class of the table’s row object. Default: |
Use the AlterAsync method, which belongs to the Table class.
You can also use Alter, which is the synchronous version of the method.
Method signature
public Task<Table<T>> AlterAsync(
IAlterTableOperation operation,
AlterTableOptions options = null
);
public Task<Table<TRowAfterAlter>> AlterAsync<TRowAfterAlter>(
IAlterTableOperation operation,
AlterTableOptions options = null
) where TRowAfterAlter : class;
| Name | Type | Summary |
|---|---|---|
|
|
The alter operation to perform. Can be one of the following:
|
|
Optional. General API options for this operation, including the timeout. For more information and examples, see Customize API interaction. |
Use the alterTable command.
Command signature
curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/TABLE_NAME" \
--header "Token: APPLICATION_TOKEN" \
--header "Content-Type: application/json" \
--data '{
"alterTable": {
"operation": {
"add": {
"columns": {
"NEW_COLUMN_NAME": "DATA_TYPE",
"NEW_COLUMN_NAME": "DATA_TYPE"
}
}
}
}
}'
curl -sS -L -X POST "API_ENDPOINT/api/json/v1/KEYSPACE_NAME/TABLE_NAME" \
--header "Token: APPLICATION_TOKEN" \
--header "Content-Type: application/json" \
--data '{
"alterTable": {
"operation": {
"drop": {
"columns": [ "COLUMN_NAME", "COLUMN_NAME" ]
}
}
}
}'
| Name | Type | Summary |
|---|---|---|
|
|
The alter operation to perform. Can be one of the following:
|
Examples
The following examples demonstrate how to alter a table.
Add columns to a table
When you add columns, the columns are defined in the same way as they are when you create a table.
After you add a column, you should index the column if you want to filter or sort on the column. For more information, see Create an index and Create a vector index.
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Python
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TypeScript
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Java
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C#
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curl
The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.
from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment
from astrapy.info import (
AlterTableAddColumns,
ColumnType,
TableScalarColumnTypeDescriptor,
)
# Get an existing table
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
"API_ENDPOINT",
token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
)
table = database.get_table("TABLE_NAME", keyspace="KEYSPACE_NAME")
# Add columns
table.alter(
AlterTableAddColumns(
columns={
"is_summer_reading": TableScalarColumnTypeDescriptor(
column_type=ColumnType.BOOLEAN,
),
"library_branch": TableScalarColumnTypeDescriptor(
column_type=ColumnType.TEXT,
),
},
),
)
import {
DataAPIClient,
UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";
// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
});
const table = database.table("TABLE_NAME", {
keyspace: "KEYSPACE_NAME",
});
// Add columns
(async function () {
await table.alter({
operation: {
add: {
columns: {
is_summer_reading: "boolean",
library_branch: "text",
},
},
},
});
})();
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.tables.Table;
import com.datastax.astra.client.tables.commands.AlterTableAddColumns;
import com.datastax.astra.client.tables.definition.rows.Row;
public class Example {
public static void main(String[] args) {
// Get an existing table
Table<Row> table =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getTable("TABLE_NAME");
// Add columns
AlterTableAddColumns alterOperation =
new AlterTableAddColumns()
.addColumnBoolean("is_summer_reading")
.addColumnText("library_branch");
table.alter(alterOperation);
}
}
-
Typed
-
Untyped
You can manually define a client-side type for your table to help statically catch errors. For more information and examples, see Custom typing for tables.
using DataStax.AstraDB.DataApi;
using DataStax.AstraDB.DataApi.Core;
using DataStax.AstraDB.DataApi.Tables;
namespace Examples;
public class ExampleRowBeforeAlter
{
[ColumnPrimaryKey(1)]
[ColumnName("title")]
public string Title { get; set; } = null!;
[ColumnPrimaryKey(2)]
[ColumnName("author")]
public string Author { get; set; } = null!;
}
public class ExampleRowAfterAlter : ExampleRowBeforeAlter
{
[ColumnName("is_summer_reading")]
public bool? IsSummerReading { get; set; }
[ColumnName("library_branch")]
public string? LibraryBranch { get; set; }
}
public class Program
{
static async Task Main()
{
// Get an existing table
var client = new DataAPIClient(
new CommandOptions() { Destination = DataAPIDestination.HCD }
);
var database = client.GetDatabase(
"API_ENDPOINT",
DataAPIClient.UsernamePasswordTokenProvider(
"USERNAME",
"PASSWORD"
),
"KEYSPACE_NAME"
);
var table = database.GetTable<ExampleRowBeforeAlter>(
"TABLE_NAME"
);
// Add columns
var newColumns = new Dictionary<string, AlterTableColumnDefinition>
{
["is_summer_reading"] = new AlterTableColumnDefinition
{
Type = "boolean",
},
["library_branch"] = new AlterTableColumnDefinition
{
Type = "text",
},
};
var alteredTable = await table.AlterAsync<ExampleRowAfterAlter>(
new AlterTableAddColumns(newColumns)
);
}
}
If you don’t pass a type parameter, the collection or table remains untyped. This is a more flexible but less type-safe option.
using DataStax.AstraDB.DataApi;
using DataStax.AstraDB.DataApi.Core;
using DataStax.AstraDB.DataApi.Tables;
namespace Examples;
public class Program
{
static async Task Main()
{
// Get an existing table
var client = new DataAPIClient(
new CommandOptions() { Destination = DataAPIDestination.HCD }
);
var database = client.GetDatabase(
"API_ENDPOINT",
DataAPIClient.UsernamePasswordTokenProvider(
"USERNAME",
"PASSWORD"
),
"KEYSPACE_NAME"
);
var table = database.GetTable("TABLE_NAME");
// Add columns
var newColumns = new Dictionary<string, AlterTableColumnDefinition>
{
["is_summer_reading"] = new AlterTableColumnDefinition
{
Type = "boolean",
},
["library_branch"] = new AlterTableColumnDefinition
{
Type = "text",
},
};
await table.AlterAsync(new AlterTableAddColumns(newColumns));
}
}
curl -sS -L -X POST "API_ENDPOINT/v1/KEYSPACE_NAME/TABLE_NAME" \
--header "Token: APPLICATION_TOKEN" \
--header "Content-Type: application/json" \
--data '{
"alterTable": {
"operation": {
"add": {
"columns": {
"is_summer_reading": "boolean",
"library_branch": "text"
}
}
}
}
}'
Add vector columns to a table
After you add a vector column, you should index the column if you want run vector searches on the column. For more information, Create a vector index.
-
Python
-
TypeScript
-
Java
-
C#
-
curl
The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.
from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment
from astrapy.info import (
AlterTableAddColumns,
TableVectorColumnTypeDescriptor,
)
# Get an existing table
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
"API_ENDPOINT",
token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
)
table = database.get_table("TABLE_NAME", keyspace="KEYSPACE_NAME")
# Add a vector column
table.alter(
AlterTableAddColumns(
columns={
"example_vector": TableVectorColumnTypeDescriptor(
dimension=1024,
),
},
)
)
import {
DataAPIClient,
UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";
// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
});
const table = database.table("TABLE_NAME", {
keyspace: "KEYSPACE_NAME",
});
// Add a vector column
(async function () {
await table.alter({
operation: {
add: {
columns: {
example_vector: { type: "vector", dimension: 1024 },
},
},
},
});
})();
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.tables.Table;
import com.datastax.astra.client.tables.commands.AlterTableAddColumns;
import com.datastax.astra.client.tables.definition.columns.TableColumnDefinitionVector;
import com.datastax.astra.client.tables.definition.rows.Row;
public class Example {
public static void main(String[] args) {
// Get an existing table
Table<Row> table =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getTable("TABLE_NAME");
// Add a vector column
AlterTableAddColumns alterOperation =
new AlterTableAddColumns()
.addColumnVector("example_vector", new TableColumnDefinitionVector().dimension(1024));
table.alter(alterOperation);
}
}
-
Typed
-
Untyped
You can manually define a client-side type for your table to help statically catch errors. For more information and examples, see Custom typing for tables.
using DataStax.AstraDB.DataApi;
using DataStax.AstraDB.DataApi.Core;
using DataStax.AstraDB.DataApi.Tables;
namespace Examples;
public abstract class ExampleRowBeforeAlter
{
[ColumnPrimaryKey(1)]
[ColumnName("title")]
public string Title { get; set; } = null!;
[ColumnPrimaryKey(2)]
[ColumnName("author")]
public string Author { get; set; } = null!;
}
public class ExampleRowAfterAlter : ExampleRowBeforeAlter
{
[ColumnName("example_vector")]
public float[]? ExampleVector { get; set; }
}
public class Program
{
static async Task Main()
{
// Get an existing table
var client = new DataAPIClient(
new CommandOptions() { Destination = DataAPIDestination.HCD }
);
var database = client.GetDatabase(
"API_ENDPOINT",
DataAPIClient.UsernamePasswordTokenProvider(
"USERNAME",
"PASSWORD"
),
"KEYSPACE_NAME"
);
var table = database.GetTable<ExampleRowBeforeAlter>(
"TABLE_NAME"
);
// Add a vector column
var newColumns = new Dictionary<
string,
AlterTableVectorColumnDefinition
>
{
["example_vector"] = new AlterTableVectorColumnDefinition
{
VectorDimension = 1024,
},
};
var alteredTable = await table.AlterAsync<ExampleRowAfterAlter>(
new AlterTableAddVectorColumns(newColumns)
);
}
}
If you don’t pass a type parameter, the collection or table remains untyped. This is a more flexible but less type-safe option.
using DataStax.AstraDB.DataApi;
using DataStax.AstraDB.DataApi.Core;
using DataStax.AstraDB.DataApi.Tables;
namespace Examples;
public class Program
{
static async Task Main()
{
// Get an existing table
var client = new DataAPIClient(
new CommandOptions() { Destination = DataAPIDestination.HCD }
);
var database = client.GetDatabase(
"API_ENDPOINT",
DataAPIClient.UsernamePasswordTokenProvider(
"USERNAME",
"PASSWORD"
),
"KEYSPACE_NAME"
);
var table = database.GetTable("TABLE_NAME");
// Add a vector column
var newColumns = new Dictionary<
string,
AlterTableVectorColumnDefinition
>
{
["example_vector"] = new AlterTableVectorColumnDefinition
{
VectorDimension = 1024,
},
};
await table.AlterAsync(new AlterTableAddVectorColumns(newColumns));
}
}
curl -sS -L -X POST "API_ENDPOINT/v1/KEYSPACE_NAME/TABLE_NAME" \
--header "Token: APPLICATION_TOKEN" \
--header "Content-Type: application/json" \
--data '{
"alterTable": {
"operation": {
"add": {
"columns": {
"example_vector": {
"type": "vector",
"dimension": 1024
}
}
}
}
}
}'
Drop columns from a table
Dropping columns produces tombstones. Excessive tombstones can impact query performance.
-
Python
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TypeScript
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Java
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C#
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curl
The following example uses untyped documents or rows, but you can define a client-side type for your collection to help statically catch errors. For examples, see Typing support.
from astrapy import DataAPIClient
from astrapy.authentication import UsernamePasswordTokenProvider
from astrapy.constants import Environment
from astrapy.info import AlterTableDropColumns
# Get an existing table
client = DataAPIClient(environment=Environment.HCD)
database = client.get_database(
"API_ENDPOINT",
token=UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
)
table = database.get_table("TABLE_NAME", keyspace="KEYSPACE_NAME")
# Drop columns
table.alter(
AlterTableDropColumns(
columns=["is_summer_reading", "library_branch"],
),
)
import {
DataAPIClient,
UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";
// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
});
const table = database.table("TABLE_NAME", {
keyspace: "KEYSPACE_NAME",
});
// Drop columns
(async function () {
await table.alter({
operation: {
drop: {
columns: ["is_summer_reading", "library_branch"],
},
},
});
})();
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.tables.Table;
import com.datastax.astra.client.tables.commands.AlterTableDropColumns;
import com.datastax.astra.client.tables.definition.rows.Row;
public class Example {
public static void main(String[] args) {
// Get an existing table
Table<Row> table =
DataAPIClients.clientHCD("USERNAME", "PASSWORD")
.getDatabase("API_ENDPOINT", "KEYSPACE_NAME")
.getTable("TABLE_NAME");
// Drop columns
AlterTableDropColumns alterOperation =
new AlterTableDropColumns("is_summer_reading", "library_branch");
table.alter(alterOperation);
}
}
-
Typed
-
Untyped
You can manually define a client-side type for your table to help statically catch errors. For more information and examples, see Custom typing for tables.
using DataStax.AstraDB.DataApi;
using DataStax.AstraDB.DataApi.Core;
using DataStax.AstraDB.DataApi.Tables;
namespace Examples;
public class ExampleRowAfterAlter
{
[ColumnPrimaryKey(1)]
[ColumnName("title")]
public string Title { get; set; } = null!;
[ColumnPrimaryKey(2)]
[ColumnName("author")]
public string Author { get; set; } = null!;
}
public class ExampleRowBeforeAlter : ExampleRowAfterAlter
{
[ColumnName("is_summer_reading")]
public bool? IsSummerReading { get; set; }
[ColumnName("library_branch")]
public string[]? LibraryBranch { get; set; }
}
public class Program
{
static async Task Main()
{
// Get an existing table
var client = new DataAPIClient(
new CommandOptions() { Destination = DataAPIDestination.HCD }
);
var database = client.GetDatabase(
"API_ENDPOINT",
DataAPIClient.UsernamePasswordTokenProvider(
"USERNAME",
"PASSWORD"
),
"KEYSPACE_NAME"
);
var table = database.GetTable<ExampleRowBeforeAlter>(
"TABLE_NAME"
);
// Drop columns
var alteredTable = await table.AlterAsync<ExampleRowAfterAlter>(
new AlterTableDropColumns(
new[] { "is_summer_reading", "library_branch" }
)
);
}
}
If you don’t pass a type parameter, the collection or table remains untyped. This is a more flexible but less type-safe option.
using DataStax.AstraDB.DataApi;
using DataStax.AstraDB.DataApi.Core;
using DataStax.AstraDB.DataApi.Tables;
namespace Examples;
public class Program
{
static async Task Main()
{
// Get an existing table
var client = new DataAPIClient(
new CommandOptions() { Destination = DataAPIDestination.HCD }
);
var database = client.GetDatabase(
"API_ENDPOINT",
DataAPIClient.UsernamePasswordTokenProvider(
"USERNAME",
"PASSWORD"
),
"KEYSPACE_NAME"
);
var table = database.GetTable("TABLE_NAME");
// Drop columns
await table.AlterAsync(
new AlterTableDropColumns(
new[] { "is_summer_reading", "library_branch" }
)
);
}
}
curl -sS -L -X POST "API_ENDPOINT/v1/KEYSPACE_NAME/TABLE_NAME" \
--header "Token: APPLICATION_TOKEN" \
--header "Content-Type: application/json" \
--data '{
"alterTable": {
"operation": {
"drop": {
"columns": ["is_summer_reading", "library_branch"]
}
}
}
}'
Client reference
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Python
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TypeScript
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Java
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C#
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curl
For more information, see the client reference.
For more information, see the client reference.
For more information, see the client reference.
For more information, see the client reference.
Client reference documentation is not applicable for HTTP.