MYSQL查看和新增表分区 1、查看表分区 SELECT partition_name part, partition_expression expr, partition_description descr, FROM_DAYS(partition_description) lessthan_sendtime, table_rows FROM INFORMATION_SCHEMA.partitions WHERE TABLE_SCHEMA =
MYSQL查看和新增表分区
1、查看表分区
SELECT
partition_name part,
partition_expression expr,
partition_description descr,
FROM_DAYS(partition_description) lessthan_sendtime,
table_rows
FROM
INFORMATION_SCHEMA.partitions
WHERE
TABLE_SCHEMA = SCHEMA()
AND TABLE_NAME='td_sendmessagelog'; ---这里是表名
2、添加表分区
ALTER TABLE td_sendmessagelog ADD PARTITION (
PARTITION p20150210 VALUES LESS THAN (TO_DAYS('2015-02-10')),
PARTITION p20150220 VALUES LESS THAN (TO_DAYS('2015-02-20')),
PARTITION p20150301 VALUES LESS THAN (TO_DAYS('2015-03-01')),
PARTITION p20150310 VALUES LESS THAN (TO_DAYS('2015-03-10')),
PARTITION p20150320 VALUES LESS THAN (TO_DAYS('2015-03-20')),
PARTITION p20150401 VALUES LESS THAN (TO_DAYS('2015-04-01')),
PARTITION p20150410 VALUES LESS THAN (TO_DAYS('2015-04-10')),
PARTITION p20150420 VALUES LESS THAN (TO_DAYS('2015-04-20')),
PARTITION p20150501 VALUES LESS THAN (TO_DAYS('2015-05-01')),
PARTITION pmax VALUES LESS THAN (maxvalue)
);
注意:创建表分区,要指定对应的列。上面例子,用的是一个时间列(sendtime)
创建表过程如下(注意指定的primary key):
create table td_sendmessagelog
(
id int not null,
sendtime datetime not null
primary key (id,sendtime)
)
创建索引:
create index Index_sid_sendtime on td_sendmessagelog
(
sid,
sendtime
);

InnoDBBufferPool reduces disk I/O by caching data and indexing pages, improving database performance. Its working principle includes: 1. Data reading: Read data from BufferPool; 2. Data writing: After modifying the data, write to BufferPool and refresh it to disk regularly; 3. Cache management: Use the LRU algorithm to manage cache pages; 4. Reading mechanism: Load adjacent data pages in advance. By sizing the BufferPool and using multiple instances, database performance can be optimized.

Compared with other programming languages, MySQL is mainly used to store and manage data, while other languages such as Python, Java, and C are used for logical processing and application development. MySQL is known for its high performance, scalability and cross-platform support, suitable for data management needs, while other languages have advantages in their respective fields such as data analytics, enterprise applications, and system programming.

MySQL is worth learning because it is a powerful open source database management system suitable for data storage, management and analysis. 1) MySQL is a relational database that uses SQL to operate data and is suitable for structured data management. 2) The SQL language is the key to interacting with MySQL and supports CRUD operations. 3) The working principle of MySQL includes client/server architecture, storage engine and query optimizer. 4) Basic usage includes creating databases and tables, and advanced usage involves joining tables using JOIN. 5) Common errors include syntax errors and permission issues, and debugging skills include checking syntax and using EXPLAIN commands. 6) Performance optimization involves the use of indexes, optimization of SQL statements and regular maintenance of databases.

MySQL is suitable for beginners to learn database skills. 1. Install MySQL server and client tools. 2. Understand basic SQL queries, such as SELECT. 3. Master data operations: create tables, insert, update, and delete data. 4. Learn advanced skills: subquery and window functions. 5. Debugging and optimization: Check syntax, use indexes, avoid SELECT*, and use LIMIT.

MySQL efficiently manages structured data through table structure and SQL query, and implements inter-table relationships through foreign keys. 1. Define the data format and type when creating a table. 2. Use foreign keys to establish relationships between tables. 3. Improve performance through indexing and query optimization. 4. Regularly backup and monitor databases to ensure data security and performance optimization.

MySQL is an open source relational database management system that is widely used in Web development. Its key features include: 1. Supports multiple storage engines, such as InnoDB and MyISAM, suitable for different scenarios; 2. Provides master-slave replication functions to facilitate load balancing and data backup; 3. Improve query efficiency through query optimization and index use.

SQL is used to interact with MySQL database to realize data addition, deletion, modification, inspection and database design. 1) SQL performs data operations through SELECT, INSERT, UPDATE, DELETE statements; 2) Use CREATE, ALTER, DROP statements for database design and management; 3) Complex queries and data analysis are implemented through SQL to improve business decision-making efficiency.

The basic operations of MySQL include creating databases, tables, and using SQL to perform CRUD operations on data. 1. Create a database: CREATEDATABASEmy_first_db; 2. Create a table: CREATETABLEbooks(idINTAUTO_INCREMENTPRIMARYKEY, titleVARCHAR(100)NOTNULL, authorVARCHAR(100)NOTNULL, published_yearINT); 3. Insert data: INSERTINTObooks(title, author, published_year)VA


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