cursor

Cursor inside SQL query

由 送分小仙女□ 提交于 2020-01-02 06:08:03
问题 In Oracle, it's possible to return a cursor inside a SQL query, using the cursor keyword, like this: select owner, table_name, cursor (select column_name from all_tab_columns where owner = allt.owner and table_name = allt.table_name) as columns from all_tables allt The questions are: Does anyone know where can I find documentation for this? Does PortgreSQL (or any other open source DBMS) have a similar feature? 回答1: It's called a CURSOR EXPRESSION, and it is documented in the obvious place,

Why do I get a pymongo.cursor.Cursor when trying to query my mongodb db via pymongo?

由 天大地大妈咪最大 提交于 2020-01-02 05:36:45
问题 I have consumed a bunch of tweets in a mongodb database. I would like to query these tweets using pymongo. For example, I would like to query for screen_name. However, when I try to do this, python does not return a tweet but a message about pymongo.cursor.Cursor. Here is my code: import sys import pymongo from pymongo import Connection connection = Connection() db = connection.test tweets = db.tweets list(tweets.find())[:1] I get a JSON, which looks like this: {u'_id': ObjectId(

Why cursorLoader didn't notify changes in source data?

由 心不动则不痛 提交于 2020-01-02 02:59:06
问题 I have a simple contentProvider, a layout with a ListView and a button for adding Items in content Provider and a CursorLoader. The http://developer.android.com/reference/android/app/LoaderManager.LoaderCallbacks.html#onLoadFinished(android.content.Loader, D) reference states that The Loader will monitor for changes to the data, and report them to you through new calls here. You should not monitor the data yourself. For example, if the data is a Cursor and you place it in a CursorAdapter, use

How get information from multiple tables using cursor?

由 允我心安 提交于 2020-01-01 19:49:07
问题 I have a query, that returns multiple tables, something like that: SELECT TableName, DatabaseName +'.'+ TableName, ColumnName FROM DBC.Columns WHERE ColumnName = 'id' And I need to loop through these tables by looking to the information stored in these tables, in order to get only specific tables. I tried something like code below, using 'LOOP' and cursor, but it says that Query is invalid (code have been taken from here): DECLARE cursor_Tables CURSOR FOR SELECT DatabaseName || '.' ||

How to set the area/rectangle in which the cursor is allowed to move?

由 半腔热情 提交于 2020-01-01 16:33:33
问题 E.g. when you hit the side of your monitor your cursor can't go any further, and more of an example is when in microsoft paint, and your choosing a colour from the RGB table, it won't allow your mouse to go outside of the rectangle while your mouse is down.. my question is how would you implement that in c++ with win32 api? 回答1: You can use the following function from Microsoft BOOL WINAPI ClipCursor( __in_opt const RECT *lpRect ); See http://msdn.microsoft.com/en-us/library/ms648383(VS.85)

Java8 ArrayList源码分析

由 孤街浪徒 提交于 2020-01-01 14:57:46
java.util.ArrayList 是最常用的工具类之一, 它是一个线程不安全的动态数组. 本文将对JDK 1.8.0中ArrayList实现源码进行简要分析. ArrayList 底层采用 Object[] 来存储, 每次添加元素前都会检查数组是否有足够空间容纳新的元素. 若数组空间不足则会进行扩容操作, 即创建一个容量更大的数组 并将已有的元素复制到新数组中. 默认情况下新数组的容量是当前容量的1.5倍. ArrayList使用 Arrays.copyOf 和 System.arraycopy 调用原生(native)方法进行数组复制, 以提高效率. addAll , removeAll 等方法中通常使用 c.toArray 方法来获取容器中所有元素. ArrayList提供了 iterator() 和 listIterator() 两种迭代器, 前者只能向后移动, 而后者可以双向移动. iterator() 只能删除上一个访问的元素, 而 listIterator() 还可以在游标位置添加元素. 两种迭代器都采用fail-fast机制, 即使用 modCount 记录结构性改变(添加删除元素等)的次数, 迭代器在移动前会检查 modCount 是否发生改变. 若 modCount 改变, 则抛出异常中止迭代. 该方法是为了防止其它线程修改容器造成迭代结果不一致.

How to setcursor position in GWT RichTextArea

由 笑着哭i 提交于 2020-01-01 10:16:15
问题 Is there a way to set the cusror position in GWT RichTextArea. There is method setCusrorPosition() to do so in TextArea, but not in RichTextArea. Perhaps there is a native JavaScript (called from GWT) that could set the cursor position in the RichTextArea? 回答1: You are right RichTextArea is not providing the setSelectionRange method, but i have created one using the JSNI. Below is the method, public native void setSelectionRange(Element elem, int pos, int length) /*-{ try { var selection =

WPF Cursor on a partially transparent image

由 核能气质少年 提交于 2020-01-01 09:19:12
问题 I have a png that contains transparent regions and I set it to the image tag but how am I able to set the cursor to a hand when it is over an opaque part of the image? Thanks Tony 回答1: To do this you will need to look at the bitmap itself. WPF's hit testing mechanism considers any pixel painted ith a "transparent" brush to still be clickable even though invisible. This is normally a good thing but gets in the way of what you're trying to do. Because a .png paints with the transparent brush,

Prevent highlighter cursor in CSS?

由 女生的网名这么多〃 提交于 2020-01-01 04:26:28
问题 I'm using <a> to make text that can be clicked and used for jQuery. I've already got CSS to make it un-highlightable: -webkit-touch-callout: none; -webkit-user-select: none; -khtml-user-select: none; -moz-user-select: none; -ms-user-select: none; user-select: none; text-decoration: none; But it still changes to the cursor shaped like a serifed "I" when it's hovered, like text usually does. Is there any way to prevent this, and preferably change it to the "hand" cursor that links normally

Sublime Text 2: How to Page Up/Down without moving the cursor

由 牧云@^-^@ 提交于 2020-01-01 04:09:26
问题 I'm on OS X 10.8.4 using ST2. When I use the Home and End keys, the viewport moves and the cursor is left alone. This is standard Mac behavior, and what I'd expect. However, when I use Page Up (pageup/pgup) and Page Down (pagedown/pgdn), the cursor moves along with the viewport. This is not how other Mac apps behave, and I'd like the cursor to be left alone for these keys too. I've been able to get this half-working by adding this to my key bindings: [ { "keys": ["pageup"], "command": "scroll
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