Class ReadOptions
ReadOptions define a read operation for a Spanner table.
Namespace: Google.Cloud.Spanner.Data
Assembly: Google.Cloud.Spanner.Data.dll
Syntax
public sealed class ReadOptionsProperties
Columns
Returns the columns that will be read from the target table. Cannot be null or empty.
Declaration
public IReadOnlyList<string> Columns { get; }Property Value
| Type | Description |
|---|---|
| IReadOnlyList<string> |
IndexName
The index to use to search and order rows from the target table if the read operation should use a different index than the primary key, or null otherwise. The rows will be returned in the order of the specified index.
Declaration
public string IndexName { get; }Property Value
| Type | Description |
|---|---|
| string |
Limit
The maximum number of rows to read from the target table, or null if there is no limit.
Declaration
public long? Limit { get; }Property Value
| Type | Description |
|---|---|
| long? |
Methods
FromColumns(IEnumerable<string>)
Creates options to read the given columns using a ReadCommand.
Declaration
public static ReadOptions FromColumns(IEnumerable<string> columns)Parameters
| Type | Name | Description |
|---|---|---|
| IEnumerable<string> | columns | The columns to read from the target table. Must not be null or empty. |
Returns
| Type | Description |
|---|---|
| ReadOptions |
FromColumns(params string[])
Creates options to read the given columns using a ReadCommand.
Declaration
public static ReadOptions FromColumns(params string[] columns)Parameters
| Type | Name | Description |
|---|---|---|
| string[] | columns | The columns to read from the target table. Must not be null or empty. |
Returns
| Type | Description |
|---|---|
| ReadOptions |
WithIndexName(string)
Returns a clone of this ReadOptions with the given index name.
Declaration
public ReadOptions WithIndexName(string indexName)Parameters
| Type | Name | Description |
|---|---|---|
| string | indexName | The index to use to search and order rows from the target table if the read operation should use a different index than the primary key. The rows will be returned in the order of the specified index. May not an empty string. Null means that the primary key of the table should be used for the read operation. |
Returns
| Type | Description |
|---|---|
| ReadOptions | A clone of this ReadOptions with the given index name. |
WithLimit(long?)
Creates a clone of this ReadOptions with the given limit.
Declaration
public ReadOptions WithLimit(long? limit)Parameters
| Type | Name | Description |
|---|---|---|
| long? | limit | The maximum number of rows to read. Must be larger than 0. Null means no limit. |
Returns
| Type | Description |
|---|---|
| ReadOptions | A clone of this ReadOptions with the given limit. |