Programmer Think

catalogue 1, Concept of array (including some shortcut key usage) 2, Two dimensional array III. Arrays tools 4, Array exception 1, Concept of array (including some shortcut key usage) A collection of multiple data of the same type arranged in a certain order 1. Characteristics of array: 1) orderly arrangement 2) the array is a varia ...

1. What is Shell Shell is a command line interpreter. It is a black window. When we issue some commands to Linux, Shell translates these commands into the actions that kernel can understand, then calls the kernel, operates the hardware, completes the operation, and then translates the signals into adult understandable forms. Shell is also a p ...

Hello, everyone~ Internet plus era, business digitization has spread to every industry you can think of. There are more and more business functions and marketing methods, and the system is more and more complex. In the face of increasingly complex business systems, the brain is less and less used So smart people put forward the design idea ...

Process oriented & object oriented Process oriented thought The steps are clear and simple. What to do in the first step and what to do in the second stepFacing the process, it is suitable to deal with some relatively simple problems Object oriented thought Birds of a feather flock together in a classified thinking mode. When thinkin ...

I. ElasticSearch document score_ Underlying principle of score calculation 1.1 step 1: boolean model According to the user's query conditions, the doc containing the specified term is filtered out first query "hello world" --> hello / world / hello & world bool --> must/must not/should --> filter --> contain / Not included ...

Presto Is an open source distributed SQL query engine, which is suitable for interactive analysis and query. The amount of data supports GB to PB bytes. Presto supports online data query, including Hive, Cassandra, relational database and proprietary data storage. A Presto query can merge data from multiple data sources and ana ...

js DOM and BOM study day 4 1. BOM overview 1.1 what is BOM BOM (Browser Object Model), Browser Object Model, which provides content independent objects that interact with browser windows. The core object is windowBOM consists of a series of objects with multiple attributes and methodsBOM lacks standards. js standard ECMA, DOM standard W3 ...

1, Gossip The weekend is coming again. Today, finish the spring blog, and then start the review of mybatis. I read it in July last year. If I don't write a blog, I'll soon forget it. Ha ha 2, Review mybatis and introduce integration methods 1. mybatis review mybatis has written a simple example before. You can take a look at the previous bl ...

Difference between fusing and degradation Many developers will be confused about the difference between fusing and downgrade. The similarities and differences between the two are summarized below. Similarities between fusing and degradation Service degradation and service fusing are similar from some angles. ·Same purpose. Both are t ...

When the flowable initializes the table, it always reports an error mismatch: library version is '6.6.0.0', db version is 5.99.0.0 Hint: Set <property name="databaseSchemaUpdate" to value="true" or value="create-drop" (use create-drop for testing only!) in bean processEngineConfiguration in flowable.cfg.xml for The database is MySQL flowa ...