MySQL stored procedure cursor error handling sample code
--set_account_data 重新生成用户编号 BEGIN DECLARE temp_id INT(8); /*用户id*/ DECLARE temp_manager INT(8); /*上级id*/ DECLARE temp_accounter_no VARCHAR(64); /*上级编码*/ DECLARE temp_max_no VARCHAR(64); /*上级的最大下级编码*/ DECLARE max_no VARCHAR(64); /*编码*/ DECLARE str1 VARCHAR(64); /*编码*/ DECLARE temp_no INT(8); /*编码*/ DECLARE temp_level INT(8); /*级次*/ DECLARE state VARCHAR(30); /*错误处理监听变量*/ /*定义用户表游标*/ DECLARE account_cursor CURSOR FOR SELECT id,manager FROM account ORDER BY manager,id; /*定义错误处理监听,用于结束游标循环*/ DECLARE CONTINUE HANDLER FOR 1329 BEGIN SET state = 'error'; END; OPEN account_cursor; REPEAT FETCH account_cursor INTO temp_id,temp_manager; IF (temp_id = 1) THEN UPDATE account SET leaf = 0,no = '01',level = 1 WHERE id = 1; ELSE /*设置上级leaf为0*/ UPDATE account SET leaf = 0 WHERE id = temp_manager; /*查询上级编号*/ SELECT no INTO temp_accounter_no FROM account WHERE id = temp_manager; /*设置上级编码*/ UPDATE account SET pno = temp_accounter_no WHERE id = temp_id; /*查询上级原有的最大下级编码*/ SELECT MAX(no) INTO temp_max_no FROM account WHERE pno = temp_accounter_no; /*如果最大下级编码为空,生成新的编码,否则把原来的编码加一*/ IF (temp_max_no IS NULL) THEN SET max_no = concat(temp_accounter_no, '0001'); ELSE SET str1 = SUBSTR(temp_max_no,LENGTH(temp_max_no)-3,4); SET temp_no = str1; SET temp_no = temp_no + 1; SET str1 = temp_no; IF (LENGTH(str1) = 1) THEN SET str1 = concat('000', str1); ELSEIF (LENGTH(str1) = 2) THEN SET str1 = concat('00', str1); ELSEIF (LENGTH(str1) = 3) THEN SET str1 = concat('0', str1); END IF; SET max_no = concat(temp_accounter_no, str1); END IF; UPDATE account SET no = max_no WHERE id = temp_id; SET temp_level = (LENGTH(max_no) + 2) / 4; UPDATE account SET level = temp_level WHERE id = temp_id; END IF; UNTIL state = 'error' END REPEAT; CLOSE account_cursor; /*修改leaf为null的为1*/ UPDATE account SET leaf = 1 WHERE leaf IS NULL; RETURN 0; END
The above is the detailed content of MySQL stored procedure cursor error handling sample code. For more information, please follow other related articles on the PHP Chinese website!

MySQLdiffersfromotherSQLdialectsinsyntaxforLIMIT,auto-increment,stringcomparison,subqueries,andperformanceanalysis.1)MySQLusesLIMIT,whileSQLServerusesTOPandOracleusesROWNUM.2)MySQL'sAUTO_INCREMENTcontrastswithPostgreSQL'sSERIALandOracle'ssequenceandt

MySQL partitioning improves performance and simplifies maintenance. 1) Divide large tables into small pieces by specific criteria (such as date ranges), 2) physically divide data into independent files, 3) MySQL can focus on related partitions when querying, 4) Query optimizer can skip unrelated partitions, 5) Choosing the right partition strategy and maintaining it regularly is key.

How to grant and revoke permissions in MySQL? 1. Use the GRANT statement to grant permissions, such as GRANTALLPRIVILEGESONdatabase_name.TO'username'@'host'; 2. Use the REVOKE statement to revoke permissions, such as REVOKEALLPRIVILEGESONdatabase_name.FROM'username'@'host' to ensure timely communication of permission changes.

InnoDB is suitable for applications that require transaction support and high concurrency, while MyISAM is suitable for applications that require more reads and less writes. 1.InnoDB supports transaction and bank-level locks, suitable for e-commerce and banking systems. 2.MyISAM provides fast read and indexing, suitable for blogging and content management systems.

There are four main JOIN types in MySQL: INNERJOIN, LEFTJOIN, RIGHTJOIN and FULLOUTERJOIN. 1.INNERJOIN returns all rows in the two tables that meet the JOIN conditions. 2.LEFTJOIN returns all rows in the left table, even if there are no matching rows in the right table. 3. RIGHTJOIN is contrary to LEFTJOIN and returns all rows in the right table. 4.FULLOUTERJOIN returns all rows in the two tables that meet or do not meet JOIN conditions.

MySQLoffersvariousstorageengines,eachsuitedfordifferentusecases:1)InnoDBisidealforapplicationsneedingACIDcomplianceandhighconcurrency,supportingtransactionsandforeignkeys.2)MyISAMisbestforread-heavyworkloads,lackingtransactionsupport.3)Memoryengineis

Common security vulnerabilities in MySQL include SQL injection, weak passwords, improper permission configuration, and unupdated software. 1. SQL injection can be prevented by using preprocessing statements. 2. Weak passwords can be avoided by forcibly using strong password strategies. 3. Improper permission configuration can be resolved through regular review and adjustment of user permissions. 4. Unupdated software can be patched by regularly checking and updating the MySQL version.

Identifying slow queries in MySQL can be achieved by enabling slow query logs and setting thresholds. 1. Enable slow query logs and set thresholds. 2. View and analyze slow query log files, and use tools such as mysqldumpslow or pt-query-digest for in-depth analysis. 3. Optimizing slow queries can be achieved through index optimization, query rewriting and avoiding the use of SELECT*.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software

ZendStudio 13.5.1 Mac
Powerful PHP integrated development environment
