Update a row (Java)
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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. |
Updates a single row in a table.
If the row does not already exist and the update includes at least one non-null or non-empty value, creates a new row.
For general information about working with tables and rows, see About tables with the Data API (Java).
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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
Updates the specified row.
If no row matches the specified primary key and the update includes at least one non-null or non-empty value, then a new row is created with the values specified $set values and primary key values.
Any omitted or $unset columns are set to null in the new row.
Does not return anything.
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A rare edge case, related to underlying Apache Cassandra® functionality, can cause a row to disappear altogether when all of its columns are set to This happens if the row was previously created from an update operation that had no pre-existing row to modify. |
Parameters
Use the updateOne method, which belongs to the com.datastax.astra.client.tables.Table class.
Method signature
void updateOne(
Filter filter,
TableUpdateOperation update
)
void updateOne(
Filter filter,
TableUpdateOperation update,
TableUpdateOneOptions options
)
| Name | Type | Summary |
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Describes the full primary key of the row to update. For this method, the filter can only use the |
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Defines the update using Data API operators. For a list of available operators and more examples, see Update operators for tables (Java). You cannot update primary key values. If you need to modify a row’s primary key, delete the row and then insert a new row with the desired primary key values. |
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General API options for this operation, including the timeout. |
Examples
The following examples demonstrate how to update a row in a table.
Update multiple columns
You can combine multiple operators and properties in a single call. For the full list of operators, see Update operators for tables (Java).
If the row does not already exist and the update includes at least one non-null or non-empty value, creates a new row.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import com.datastax.astra.client.tables.Table;
import com.datastax.astra.client.tables.commands.TableUpdateOperation;
import com.datastax.astra.client.tables.definition.rows.Row;
import java.util.Arrays;
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");
// Update a row
Filter filter =
Filters.and(
Filters.eq("title", "Hidden Shadows of the Past"),
Filters.eq("author", "John Anthony"));
TableUpdateOperation update =
new TableUpdateOperation()
.set("rating", 4.5)
.set("genres", Arrays.asList("Fiction", "Drama"))
.unset("borrower");
table.updateOne(filter, update);
}
}
Unset columns
To unset a column, you can use the $unset operator, or you can use the $set operator and an empty value.
Either operation will delete the value in the specified column.
Unsetting a column produces a tombstone. Excessive tombstones can impact query performance.
import com.datastax.astra.client.DataAPIClients;
import com.datastax.astra.client.core.query.Filter;
import com.datastax.astra.client.core.query.Filters;
import com.datastax.astra.client.tables.Table;
import com.datastax.astra.client.tables.commands.TableUpdateOperation;
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");
// Update a row
Filter filter =
Filters.and(
Filters.eq("title", "Hidden Shadows of the Past"),
Filters.eq("author", "John Anthony"));
TableUpdateOperation update = new TableUpdateOperation().unset("genres");
table.updateOne(filter, update);
}
}
Client reference
For more information, see the client reference.