ContentResolver.Query Method
Definition
Important
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Overloads
| Query(Uri, String[], Bundle, CancellationSignal) |
Query the given URI, returning a |
| Query(Uri, String[], String, String[], String) |
Query the given URI, returning a |
| Query(Uri, String[], String, String[], String, CancellationSignal) |
Query the given URI, returning a |
Query(Uri, String[], Bundle, CancellationSignal)
Query the given URI, returning a Cursor over the result set
with support for cancellation.
[Android.Runtime.Register("query", "(Landroid/net/Uri;[Ljava/lang/String;Landroid/os/Bundle;Landroid/os/CancellationSignal;)Landroid/database/Cursor;", "", ApiSince=26)]
public Android.Database.ICursor? Query (Android.Net.Uri uri, string[]? projection, Android.OS.Bundle? queryArgs, Android.OS.CancellationSignal? cancellationSignal);[<Android.Runtime.Register("query", "(Landroid/net/Uri;[Ljava/lang/String;Landroid/os/Bundle;Landroid/os/CancellationSignal;)Landroid/database/Cursor;", "", ApiSince=26)>]
member this.Query : Android.Net.Uri * string[] * Android.OS.Bundle * Android.OS.CancellationSignal -> Android.Database.ICursorParameters
- uri
- Uri
The URI, using the content:// scheme, for the content to retrieve.
- projection
- String[]
A list of which columns to return. Passing null will return all columns, which is inefficient.
- queryArgs
- Bundle
A Bundle containing additional information necessary for
the operation. Arguments may include SQL style arguments, such
as ContentResolver#QUERY_ARG_SQL_LIMIT, but note that
the documentation for each individual provider will indicate
which arguments they support.
- cancellationSignal
- CancellationSignal
A signal to cancel the operation in progress, or null if none.
If the operation is canceled, then OperationCanceledException will be thrown
when the query is executed.
Returns
A Cursor object, which is positioned before the first entry. May return
null if the underlying content provider returns null,
or if it crashes.
- Attributes
Remarks
Query the given URI, returning a Cursor over the result set with support for cancellation.
For best performance, the caller should follow these guidelines:
<li>Provide an explicit projection, to prevent reading data from storage that aren't going to be used.
Provider must identify which QUERY_ARG_SORT* arguments were honored during the preparation of the result set by including the respective argument keys in the Cursor extras Bundle. See #EXTRA_HONORED_ARGS for details.
Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.
Applies to
Query(Uri, String[], String, String[], String)
Query the given URI, returning a Cursor over the result set.
[Android.Runtime.Register("query", "(Landroid/net/Uri;[Ljava/lang/String;Ljava/lang/String;[Ljava/lang/String;Ljava/lang/String;)Landroid/database/Cursor;", "")]
public Android.Database.ICursor? Query (Android.Net.Uri uri, string[]? projection, string? selection, string[]? selectionArgs, string? sortOrder);[<Android.Runtime.Register("query", "(Landroid/net/Uri;[Ljava/lang/String;Ljava/lang/String;[Ljava/lang/String;Ljava/lang/String;)Landroid/database/Cursor;", "")>]
member this.Query : Android.Net.Uri * string[] * string * string[] * string -> Android.Database.ICursorParameters
- uri
- Uri
The URI, using the content:// scheme, for the content to retrieve.
- projection
- String[]
A list of which columns to return. Passing null will return all columns, which is inefficient.
- selection
- String
A filter declaring which rows to return, formatted as an SQL WHERE clause (excluding the WHERE itself). Passing null will return all rows for the given URI.
- selectionArgs
- String[]
You may include ?s in selection, which will be replaced by the values from selectionArgs, in the order that they appear in the selection. The values will be bound as Strings.
- sortOrder
- String
How to order the rows, formatted as an SQL ORDER BY clause (excluding the ORDER BY itself). Passing null will use the default sort order, which may be unordered.
Returns
A Cursor object, which is positioned before the first entry. May return
null if the underlying content provider returns null,
or if it crashes.
- Attributes
Remarks
Query the given URI, returning a Cursor over the result set.
For best performance, the caller should follow these guidelines: <ul> <li>Provide an explicit projection, to prevent reading data from storage that aren't going to be used.</li> <li>Use question mark parameter markers such as 'phone=?' instead of explicit values in the selection parameter, so that queries that differ only by those values will be recognized as the same for caching purposes.</li> </ul>
Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.
See also
Applies to
Query(Uri, String[], String, String[], String, CancellationSignal)
Query the given URI, returning a Cursor over the result set
with optional support for cancellation.
[Android.Runtime.Register("query", "(Landroid/net/Uri;[Ljava/lang/String;Ljava/lang/String;[Ljava/lang/String;Ljava/lang/String;Landroid/os/CancellationSignal;)Landroid/database/Cursor;", "")]
public Android.Database.ICursor? Query (Android.Net.Uri uri, string[]? projection, string? selection, string[]? selectionArgs, string? sortOrder, Android.OS.CancellationSignal? cancellationSignal);[<Android.Runtime.Register("query", "(Landroid/net/Uri;[Ljava/lang/String;Ljava/lang/String;[Ljava/lang/String;Ljava/lang/String;Landroid/os/CancellationSignal;)Landroid/database/Cursor;", "")>]
member this.Query : Android.Net.Uri * string[] * string * string[] * string * Android.OS.CancellationSignal -> Android.Database.ICursorParameters
- uri
- Uri
The URI, using the content:// scheme, for the content to retrieve.
- projection
- String[]
A list of which columns to return. Passing null will return all columns, which is inefficient.
- selection
- String
A filter declaring which rows to return, formatted as an SQL WHERE clause (excluding the WHERE itself). Passing null will return all rows for the given URI.
- selectionArgs
- String[]
You may include ?s in selection, which will be replaced by the values from selectionArgs, in the order that they appear in the selection. The values will be bound as Strings.
- sortOrder
- String
How to order the rows, formatted as an SQL ORDER BY clause (excluding the ORDER BY itself). Passing null will use the default sort order, which may be unordered.
- cancellationSignal
- CancellationSignal
A signal to cancel the operation in progress, or null if none.
If the operation is canceled, then OperationCanceledException will be thrown
when the query is executed.
Returns
A Cursor object, which is positioned before the first entry. May return
null if the underlying content provider returns null,
or if it crashes.
- Attributes
Remarks
Query the given URI, returning a Cursor over the result set with optional support for cancellation.
For best performance, the caller should follow these guidelines: <ul> <li>Provide an explicit projection, to prevent reading data from storage that aren't going to be used.</li> <li>Use question mark parameter markers such as 'phone=?' instead of explicit values in the selection parameter, so that queries that differ only by those values will be recognized as the same for caching purposes.</li> </ul>
Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons 2.5 Attribution License.