ADO 记录集对象
记录集对象
ADO Recordset 对象用于保存数据库表中的一组记录。 Recordset 对象由记录和列（字段）组成。
在 ADO 中，该对象是最重要的，也是最常用于操作数据库中的数据的对象。
程序ID
set objRecordset=Server.CreateObject("ADODB.recordset")
Recordset 对象可以支持两种类型的更新：
- 即时更新- 一旦调用 Update 方法，所有更改都会立即写入数据库。
- 批量更新- 提供程序将缓存多个更改，然后使用 UpdateBatch 方法将它们发送到数据库。
在 ADO 中定义了 4 种不同的游标类型：
- 动态光标- 允许您查看其他用户的添加、更改和删除。
- 键集光标 -与动态游标类似，不同之处在于您无法看到其他用户添加的内容，并且它会阻止访问其他用户已删除的记录。其他用户的数据更改仍然可见。
- 静态光标- 提供记录集的静态副本，供您用来查找数据或生成报告。其他用户的添加、更改或删除将不可见。这是打开客户端 Recordset 对象时允许的唯一游标类型。
- 只进光标- 允许您仅向前滚动记录集。其他用户的添加、更改或删除将不可见。
光标类型可以通过 CursorType 属性或 Open 方法中的 CursorType 参数设置。
笔记：并非所有提供程序都支持 Recordset 对象的所有方法或属性。
特性
| Property | Description |
|---|---|
| AbsolutePage | Sets or returns a value that specifies the page number in the Recordset object |
| AbsolutePosition | Sets or returns a value that specifies the ordinal position of the current record in the Recordset object |
| ActiveCommand | Returns the Command object associated with the Recordset |
| ActiveConnection | Sets or returns a definition for a connection if the connection is closed, or the current Connection object if the connection is open |
| BOF | Returns true if the current record position is before the first record, otherwise false |
| Bookmark | Sets or returns a bookmark. The bookmark saves the position of the current record |
| CacheSize | Sets or returns the number of records that can be cached |
| CursorLocation | Sets or returns the location of the cursor service |
| CursorType | Sets or returns the cursor type of a Recordset object |
| DataMember | Sets or returns the name of the data member that will be retrieved from the object referenced by the DataSource property |
| DataSource | Specifies an object containing data to be represented as a Recordset object |
| EditMode | Returns the editing status of the current record |
| EOF | Returns true if the current record position is after the last record, otherwise false |
| Filter | Sets or returns a filter for the data in a Recordset object |
| Index | Sets or returns the name of the current index for a Recordset object |
| LockType | Sets or returns a value that specifies the type of locking when editing a record in a Recordset |
| MarshalOptions | Sets or returns a value that specifies which records are to be returned to the server |
| MaxRecords | Sets or returns the maximum number of records to return to a Recordset object from a query |
| PageCount | Returns the number of pages with data in a Recordset object |
| PageSize | Sets or returns the maximum number of records allowed on a single page of a Recordset object |
| RecordCount | Returns the number of records in a Recordset object |
| Sort | Sets or returns the field names in the Recordset to sort on |
| Source | Sets a string value or a Command object reference, or returns a String value that indicates the data source of the Recordset object |
| State | Returns a value that describes if the Recordset object is open, closed, connecting, executing or retrieving data |
| Status | Returns the status of the current record with regard to batch updates or other bulk operations |
| StayInSync | Sets or returns whether the reference to the child records will change when the parent record position changes |
方法
| Method | Description |
|---|---|
| AddNew | Creates a new record |
| Cancel | Cancels an execution |
| CancelBatch | Cancels a batch update |
| CancelUpdate | Cancels changes made to a record of a Recordset object |
| Clone | Creates a duplicate of an existing Recordset |
| Close | Closes a Recordset |
| CompareBookmarks | Compares two bookmarks |
| Delete | Deletes a record or a group of records |
| Find | Searches for a record in a Recordset that satisfies a specified criteria |
| GetRows | Copies multiple records from a Recordset object into a two-dimensional array |
| GetString | Returns a Recordset as a string |
| Move | Moves the record pointer in a Recordset object |
| MoveFirst | Moves the record pointer to the first record |
| MoveLast | Moves the record pointer to the last record |
| MoveNext | Moves the record pointer to the next record |
| MovePrevious | Moves the record pointer to the previous record |
| NextRecordset | Clears the current Recordset object and returns the next Recordset object by looping through a series of commands |
| Open | Opens a database element that gives you access to records in a table, the results of a query, or to a saved Recordset |
| Requery | Updates the data in a Recordset by re-executing the query that made the original Recordset |
| Resync | Refreshes the data in the current Recordset from the original database |
| Save | Saves a Recordset object to a file or a Stream object |
| Seek | Searches the index of a Recordset to find a record that matches the specified values |
| Supports | Returns a boolean value that defines whether or not a Recordset object supports a specific type of functionality |
| Update | Saves all changes made to a single record in a Recordset object |
| UpdateBatch | Saves all changes in a Recordset to the database. Used when working in batch update mode |
活动
笔记：不能使用 VBScript 或 JScript 处理事件（只有 Visual Basic、Visual C++ 和 Visual J++ 语言可以处理事件）。
| Event | Description |
|---|---|
| EndOfRecordset | Triggered when you try to move to a record after the last record |
| FetchComplete | Triggered after all records in an asynchronous operation have been fetched |
| FetchProgress | Triggered periodically in an asynchronous operation, to state how many more records that have been fetched |
| FieldChangeComplete | Triggered after the value of a Field object change |
| MoveComplete | Triggered after the current position in the Recordset has changed |
| RecordChangeComplete | Triggered after a record has changed |
| RecordsetChangeComplete | Triggered after the Recordset has changed |
| WillChangeField | Triggered before the value of a Field object change |
| WillChangeRecord | Triggered before a record change |
| WillChangeRecordset | Triggered before a Recordset change |
| WillMove | Triggered before the current position in the Recordset changes |
收藏
| Collection | Description |
|---|---|
| Fields | Indicates the number of Field objects in the Recordset object |
| Properties | Contains all the Property objects in the Recordset object |
Fields 集合的属性
| Property | Description |
|---|---|
| Count | Returns the number of items in the fields collection. Starts at zero. Example: countfields=rs.Fields.Count |
| Item(named_item/number) | Returns a specified item in the fields collection. Example: itemfields=rs.Fields.Item(1) |
属性集合的属性
| Property | Description |
|---|---|
| Count | Returns the number of items in the properties collection. Starts at zero. Example: countprop=rs.Properties.Count |
| Item(named_item/number) | Returns a specified item in the properties collection. Example: itemprop = rs.Properties.Item(1) |