sql vs nosql pros and cons

the exact same statement, the next execution of SQL will be compiled again. This behavior is called "recompile (RECOMPILE)". The compilation and recompilation of the execution plan are all resources consuming. If the execution plan can be reused, then SQL Server does not need to perform the above process to speed up the execution of instructions, and many of the statement tuning articles refer to the data

The pros and cons of 8.4.5 indexes and how to determine whether an index is needed I believe readers know that indexing can greatly improve the efficiency of data retrieval, so that query executes faster, but probably not every friend knows that indexing greatly improves the efficiency of retrieval, but also brings some negative effects on the database. The following is a simple analysis of the advantages

just a simple remote procedure call. Distributed systems also mean that developers need to consider network latency, fault tolerance, message serialization, unreliable networks, asynchrony, versioning, load, and so on, while faced with so many microservices need to be distributed, the entire product needs to have a complete set of mechanisms to ensure that each service can function properly. transactional, asynchronous, test-facing challengesCross-process transactions, large amounts of asynch

Tags: hibernate1.Analyze The pros and cons of hibernate and jdbc advantages and disadvantages of JDBCDisadvantages1, query code is particularly cumbersome2, repetitive code is very much, frequent try,catch3, do not do the data cache4 . Poor portability of SQL (MySQL statement cannot be used in Oracle)AdvantagesFast speedBetter control.Benefits and drawbacks of hi

need to be adjusted. Repetitive labor The same functionality may be used in many services. This function point is not large enough to provide a service level, this time may be different service teams will develop this function alone, duplicate business logic, which violates a good software engineering many principles. Complexity of distributed systems Micro Services connect different services through rest APIs or messages, which may have been a simple remote procedure call before. Distribut

performance barriers:2) Session Bean A schema that uses Hibernate to improve the development efficiency of the above architecture:3) Session Bean The above 3 architectures are analyzed:1. Memory consumption: The JDBC Architecture 2 is undoubtedly the most memory-saving, hibernate architecture is the second, EB Architecture 1 is the worst.2, operating efficiency: If JDBC code write is very optimized, then the JDBC schema is the most efficient, but the actual project, this is almost impossible, w

table from one or more tables, which is actually a query result, and the query that corresponds to the name and view of the view is stored in the data dictionary.(2). What are the pros and cons of views?A. Data security.Define different views for different users so that users can only see data about themselves. The database Authorization command enables each user to limit the retrieval of a database to a s

SSH project, what is the difference between using gethibernatetemplate and getsession? What are the pros and cons, thanks for the answer!Reward Points: 0-resolution Time: 2008-10-7 09:42SSH project, what is the difference between using gethibernatetemplate and getsession? What are the pros and cons, thanks for the answ

to send an asynchronous request to the server via the XMLHttpRequest object, get the data from the server, and then use JavaScript to manipulate the DOM and update the page. One of the most critical steps is getting the request data from the server. To understand this process and principle, we must have some knowledge of xmlhttprequest.XMLHttpRequest is the core mechanism of Ajax, which was first introduced in IE5 and is a technique that supports asynchronous requests. Simply put, JavaScript ca

standards of the Web.5.AJAX points of attention and applicable and non-applicable scenarios(1). Attention PointWhen Ajax is developed, network latency-that is, the interval between a user sending a request to a server to make a response-requires careful consideration. Not giving users a clear response, without proper pre-reading data, or improper handling of XMLHttpRequest, will make users feel delayed, which users do not want to see, but they do not understand. A common solution is to use a vi

complex point query Statements (tables, multiple subqueries, conditional mates) is very painful, and to use the tool to see whether the generated statements are logical, and can not be constantly debugging (I think the function is debugging out, the brain hole big open people can skip);EF Replacement version is really a pit, if you want to upgrade the program's EF from the lower version to the higher version, the higher version will be less than many methods (see the data is clearly written sql

of the Web.5.AJAX points of attention and applicable and non-applicable scenarios(1). Attention PointWhen Ajax is developed, network latency-that is, the interval between a user sending a request to a server to make a response-requires careful consideration. Not giving users a clear response, without proper pre-reading data, or improper handling of XMLHttpRequest, will make users feel delayed, which users do not want to see, but they do not understand. A common solution is to use a visual compo

) data name: (NSString ) fileName{NSString *path = [self filepath:filename];[data writeToFile:path atomically:YES];}Get file path+ (nsstring*) FilePath: (nsstring*) FileName {nsarray* mypaths = Nssearchpathfordirectoriesindomains (NSDocumentDirectory, Nsuserdomainmask, YES);nsstring* Mydocpath = [Mypaths objectatindex:0];nsstring* FilePath = [Mydocpath stringbyappendingpathcomponent:filename];return filePath;}Fourth method: Database storageThe library for SQLite is preset in the iOS SDK. Develo

null values in the database, and NULL is always the first in ascending order, so for different partition types, The MySQL database also handles null differently. For a range partition, if NULL is inserted into the partition column, the MySQL database puts the value in the leftmost partition, noting that if the partition is deleted, all content under the partition is deleted from the disk, the null partition is removed, and the null value is then deleted. To use null under the list partition, yo

const, EQ_REF, ref, range, index, and all, means that all records in the data table must be read once, corresponding to each record in the previous data table- This situation can often be avoided by an index).The Possible_keys data column gives the various indexes that MySQL can use when searching for data records. The Key data column is the actual mysql-selected index, which is given in the Key_len data column for the length of the byte count. For example, for an index of an integer data colum

Tags: mysql database large number MySQL DAO net reliable server user TenCommon relational databases are: IBM DB2, ORACLE, Sybase, SQL Server, MySQL, Access, today we focus on Oracel, SQL Server, MySQL three big database. Oracle databases are designed for larger project development with complex business logic and large data volumes. The SQL Server database feature

Task:Grilled all the pros and cons of all technologyJPA, this rotten thing.Http://www.blogjava.net/jobs/archive/2008/02/02/178917.htmlFirst, before we know what the benefits of LINQ to SQL are, it's important to understand why Microsoft has made such a thing first. What is the purpose of this thing:--of course, to meet programmers who do not know how to manipulat

Types and pros and cons of MySQL indexesAn index is a special kind of file (an index on a InnoDB data table is an integral part of a table space), and they contain reference pointers to all records in the datasheet.Note: [1] The index is not omnipotent! Indexing can speed up data retrieval operations, but it slows down data modification operations. Each time a data record is modified, the index must be refr