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Usually when we refer to database table structure, we are concerned about several attributes:Field name, type, length, whether primary key, whether self-increasing, whether empty, default value, notes.So, what are the properties of using SQL statements to get these attributes under the mainstream databases? MySQL database As the most popular da ...

Summary Pg_stat_states is an extension plug-in of PostgreSQL database, which is used to collect the running information of SQL in the database, such as the total execution time of SQL, the number of calls, the hit rate of shared memory and so on. Used to monitor the performance of database is an important expansion module of database performanc ...

Label PostgreSQL, json, string escape, unicode, SQL injection, backslash_quote, escape_string_warning, standard_conforming_strings background Through this article, you can understand: 1. How to input special characters in a string, such as carriage return. 2. How to enter single quotation marks in a string. 3. What is an escape character? Us ...

Label PostgreSQL, 10.0, sharding, distributed transaction, 2pc, two-phase transaction background As a complete distributed database (sharding), it is not possible without distributed transaction support. What is distributed transaction? For example, we compare a database to a child, each child has 100 yuan, and then children A give children ...

Label PostgreSQL, Fuzzy Query, Regular Query, pg_trgm, bytea, gin, Functional Index background Pre-fuzziness (with prefix fuzziness), post-fuzziness (with suffix fuzziness), pre-and post-fuzziness (without prefix fuzziness), and regular matching are common requirements in the field of text search. PostgreSQL has a strong text search capabili ...

Introduction: Harbor is an enterprise Registry server for storing and distributing Docker images that extends the open source Docker Distribution by adding some of the features necessary for the enterprise, such as security, identity, and management.As an enterprise private Registry server, Harbor provides better performance and security.Enhan ...

Label PostgreSQL, pg_xlogdump, database profile background It is convenient to view TOP SQL in PostgreSQL, as follows: PostgreSQL How to Find TOP SQL (e.g. IO-consumed SQL) From another point of view, such as REDO files, we can also analyze the operation type of the database in each period, analyze the resource consumption of the database, a ...

Label PostgreSQL, window function, vehicle networking, trajectory, trajectory cleaning, lag, lead background A typical scenario in Vehicle Networking is to collect the trajectories of vehicles. Generally speaking, the trajectories of vehicles are not reported in real time, and may accumulate a number of trajectory records, or how often to re ...

Label PostgreSQL, Heming Distance, Smlar, GiST Index background http://www.cnblogs.com/lushilin/p/6549665.html Application of SimHash Through the above steps, we can use SimHash algorithm to generate a vector fingerprint for each web page, so the question arises, how to judge the similarity of two texts? This is mainly applied to Heming di ...

background The data also have eight characters of birthdays, do you believe it? How do elements and columns, rows and rows interrelate? Is the query slow? Don't believe that everything is destined by heaven. How to change the data? After reading this article, you can do it. One talent, nine efforts. Fate is destined. The destiny is decided b ...