2016 年 12月随笔档案 - huey2672

JavaScript - Scope of variables

摘要：It's important to note, especially if you have come to JavaScript from another language, that variables in JavaScript are not defined in a block scope 阅读全文

posted @ 2016-12-13 20:34 huey2672 阅读(310) 评论(0) 推荐(0)

SQL - 查询某一字段值相同而另一字段值最大的记录

摘要：有时需要以某一字段作为分组，筛选每一组的另一字段值最大（或最小）的记录。例如，有如下表 app，存储了 app 的 ID、名称、版本号等信息。现在要筛选出每个 app 版本最大的记录。方法一方法二方法三方法四阅读全文

posted @ 2016-12-08 17:10 huey2672 阅读(5831) 评论(1) 推荐(1)

Table of Contents - Python 2.x

摘要：异常异常类的继承关系日志标准日志模块 Hello World Logging Configuration 阅读全文

posted @ 2016-12-08 17:01 huey2672 阅读(296) 评论(0) 推荐(0)

MongoDB - Introduction to MongoDB, Databases and Collections

摘要：MongoDB stores BSON documents, i.e. data records, in collections; the collections in databases. Databases In MongoDB, databases hold collections of do 阅读全文

posted @ 2016-12-08 17:01 huey2672 阅读(407) 评论(0) 推荐(0)

MongoDB - MongoDB CRUD Operations, Bulk Write Operations

摘要：Overview MongoDB provides clients the ability to perform write operations in bulk. Bulk write operations affect a singlecollection. MongoDB allows app 阅读全文

posted @ 2016-12-05 11:34 huey2672 阅读(659) 评论(0) 推荐(0)

MongoDB - MongoDB CRUD Operations, Delete Documents

摘要：Delete Methods MongoDB provides the following methods to delete documents of a collection: Delete at most a single document that match a specified fil 阅读全文

posted @ 2016-12-05 10:39 huey2672 阅读(951) 评论(0) 推荐(0)

MongoDB - MongoDB CRUD Operations, Insert Documents

摘要：MongoDB provides the following methods for inserting documents into a collection: db.collection.insertOne() db.collection.insertMany() db.collection.i 阅读全文

posted @ 2016-12-05 10:01 huey2672 阅读(400) 评论(0) 推荐(0)

MongoDB - MongoDB CRUD Operations, Update Documents

摘要：Update Methods MongoDB provides the following methods for updating documents in a collection: Updates at most a single document that match a specified 阅读全文

posted @ 2016-12-01 21:12 huey2672 阅读(731) 评论(0) 推荐(0)

MongoDB - MongoDB CRUD Operations, Query Documents, Iterate a Cursor in the mongo Shell

摘要：The db.collection.find() method returns a cursor. To access the documents, you need to iterate the cursor. However, in the mongo shell, if the returne 阅读全文

posted @ 2016-12-01 06:43 huey2672 阅读(382) 评论(0) 推荐(0)

MongoDB - MongoDB CRUD Operations, Query Documents, Query for Null or Missing Fields

摘要：Different query operators in MongoDB treat null values differently. The examples on this page use the db.collection.find() method in the mongo shell. 阅读全文

posted @ 2016-12-01 06:13 huey2672 阅读(192) 评论(0) 推荐(0)

MongoDB - MongoDB CRUD Operations, Query Documents, Project Fields to Return from Query

摘要：By default, queries in MongoDB return all fields in matching documents. To limit the amount of data that MongoDB sends to applications, you can includ 阅读全文

posted @ 2016-12-01 05:56 huey2672 阅读(366) 评论(0) 推荐(0)

MongoDB - MongoDB CRUD Operations, Query Documents

摘要：Query Method MongoDB provides the db.collection.find() method to read documents from a collection. The db.collection.find() method returns a cursor to 阅读全文

posted @ 2016-12-01 05:31 huey2672 阅读(344) 评论(0) 推荐(0)

MongoDB - MongoDB CRUD Operations

摘要：CRUD operations create, read, update, and delete documents. Create Operations Create or insert operations add new documents to a collection. If the co 阅读全文

posted @ 2016-12-01 03:05 huey2672 阅读(252) 评论(0) 推荐(0)

MongoDB - The mongo Shell, mongo Shell Quick Reference

摘要：mongo Shell Command History You can retrieve previous commands issued in the mongo shell with the up and down arrow keys. Command history is stored in 阅读全文

posted @ 2016-12-01 02:14 huey2672 阅读(288) 评论(0) 推荐(0)

MongoDB - The mongo Shell, Data Types in the mongo Shell

摘要：MongoDB BSON provides support for additional data types than JSON. Drivers provide native support for these data types in host languages and the mongo 阅读全文

posted @ 2016-12-01 00:58 huey2672 阅读(298) 评论(0) 推荐(0)

MongoDB - The mongo Shell, Write Scripts for the mongo Shell

摘要：You can write scripts for the mongo shell in JavaScript that manipulate data in MongoDB or perform administrative operation. For more information abou 阅读全文

posted @ 2016-12-01 00:35 huey2672 阅读(441) 评论(0) 推荐(0)

MongoDB - The mongo Shell, Access the mongo Shell Help

摘要：In addition to the documentation in the MongoDB Manual, the mongo shell provides some additional information in its “online” help system. This documen 阅读全文

posted @ 2016-12-01 00:02 huey2672 阅读(222) 评论(0) 推荐(0)