How To Debug Mysql Error
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I see many questions on StackOverflow about database issues. This post aims to provide a checklist to help diagnose common issues. While this post contains PHP php mysqli error and MySQL code samples, this debugging checklist applies to other database platforms. First,
I Cannot Select Mysql Database
debugging is hard. Especially debugging database issues. Often times the best approach is to systematically rule out what cannot mysql error 1045 be the problem. This checklist adopts such an approach from a low to high level. Can you connect to the database outside your application? Verify you can connect to your database by
Debug Mysql Query
logging into MySQL from the command line. mysql -u dbuser -p -h localhost database If you have a specific database user for your application, be sure to verify their credentials as well. If you do not have command line access, you can use another database administration tool (e.g. PHPMyAdmin). If you cannot connect to the database, you need to start at the beginning: mysql error 1064 Ensure MySQL is running, your database exists, and your credentials are correct. Can you connect to the database inside your application? Verify you can connect to the database from PHP. Test with a separate script to also rule out bugs in your codebase: query($sql)) { echo 'Error: ', $mysqli->error; } In this case, we’d see that $bad_var is not set. As such, the query becomes:
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Can't Connect To Local Mysql Server Through Socket
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Issues Security Guidelines Keeping Passwords Secure End-User Guidelines for Password Security Administrator Guidelines for Password Security Passwords column count doesn't match value count at row 1 and Logging Password Hashing in MySQL Making MySQL Secure Against Attackers Security-Related mysqld Options and Variables How to Run MySQL as a Normal User Security Issues with LOAD DATA http://jason.pureconcepts.net/2013/04/common-debugging-php-mysql/ LOCAL Client Programming Security Guidelines The MySQL Access Privilege System Privileges Provided by MySQL Grant Tables Specifying Account Names Access Control, Stage 1: Connection Verification Access Control, Stage 2: Request Verification When Privilege Changes Take Effect Troubleshooting Problems Connecting to MySQL MySQL User Account Management User Names and Passwords Adding User Accounts Removing User Accounts Setting Account Resource Limits https://dev.mysql.com/doc/refman/5.7/en/problems-connecting.html Assigning Account Passwords Password Expiration Policy Password Expiration and Sandbox Mode Pluggable Authentication Proxy Users User Account Locking SQL-Based MySQL Account Activity Auditing Using Secure Connections OpenSSL Versus yaSSL Building MySQL with Support for Secure Connections Secure Connection Protocols and Ciphers Configuring MySQL to Use Secure Connections Command Options for Secure Connections Creating SSL and RSA Certificates and Keys Creating SSL and RSA Certificates and Keys using MySQL Creating SSL Certificates and Keys Using openssl Creating RSA Keys Using openssl Connecting to MySQL Remotely from Windows with SSH Security Plugins Authentication Plugins The Native Authentication Plugin The Old Native Authentication Plugin Migrating Away from Pre-4.1 Password Hashing and the mysql_old_password Plugin The SHA-256 Authentication Plugin The PAM Authentication Plugin The Windows Native Authentication Plugin The No-Login Authentication Plugin The Cleartext Client-Side Authentication Plugin The Socket Peer-Credential Authentication Plugin The Test Authentication Plugin The Password Validation Plugin Password Validation Plugin Installation Password Validation Plugin Options and Variables The MySQL Keyring Keyring Plugin Installation Configuring the keyring_file File-Based Plugin Configuring the keyring_okv Oracle Key Vault
21st, 2013 176,158 mysql mariadb log performance databases memcached sysadmin Debian how-to Share: Tweet Image source: Blue and pink dolphins at work If you are a web developer, http://www.pontikis.net/blog/how-and-when-to-enable-mysql-logs you need to refer to various log files, in order to debug your application or improve its performance. Logs is the best place to start troubleshooting. Concerning the famous MySQL database server (or MariaDB https://github.com/mysqljs/mysql server), you need to refer to the following log files: The Error Log. It contains information about errors that occur while the server is running (also server start and stop) The General Query Log. This mysql error is a general record of what mysqld is doing (connect, disconnect, queries) The Slow Query Log. Ιt consists of "slow" SQL statements (as indicated by its name). This article does not refer to The Binary Log. This requires very high standards server hardware and is useful only in special cases (e.g. replication, master - slaves setup, certain data recovery operations). Οtherwise, it is just a "performance killer". The official documentation how to debug about MySQL logs is available here. Enable logs from MySQL configuration Logging parameters are located under [mysqld] section. Edit MySQL configuration file: nano /etc/mysql/my.cnf This is the default setup for Logging and Replication (in Debian server). In other distributions the structure may be different, but you can always use MySQL server parameters: # * Logging and Replication # # Both location gets rotated by the cronjob. # Be aware that this log type is a performance killer. # As of 5.1 you can enable the log at runtime! #general_log_file = /var/log/mysql/mysql.log #general_log = 1 # # Error logging goes to syslog due to /etc/mysql/conf.d/mysqld_safe_syslog.cnf. # # Here you can see queries with especially long duration #log_slow_queries = /var/log/mysql/mysql-slow.log #long_query_time = 2 #log-queries-not-using-indexes # # The following can be used as easy to replay backup logs or for replication. # note: if you are setting up a replication slave, see README.Debian about # other settings you may need to change. #server-id = 1 #log_bin = /var/log/mysql/mysql-bin.log expire_logs_days = 10 max_binlog_size = 100M #binlog_do_db = include_database_name #binlog_ignore_db = include_database_name All log files are NOT enabled by default MySQL setup (except the error log on Windows). Default Debian setup sends Error log to syslog. The other log files are n
Sign in Pricing Blog Support Search GitHub This repository Watch 423 Star 7,824 Fork 1,258 mysqljs/mysql Code Issues 87 Pull requests 18 Projects 0 Wiki Pulse Graphs A pure node.js JavaScript Client implementing the MySql protocol. 1,067 commits 28 branches 53 releases Fetching contributors MIT JavaScript 100.0% JavaScript Clone or download Clone with HTTPS Use Git or checkout with SVN using the web URL. Open in Desktop Download ZIP Find file Branch: master Switch branches/tags Branches Tags change-user combine-diag connection_state debug feature/reset-connection-packet gh-142-driver-stalls-on-reconnect master multiple-results new-default-encoding oldpw pipe pool pr/351 prepare-mysql2 prepare procedure_calls refactor-handshake refactor refactoring server tls-stream transaction_api user_plugins utest v0.9 v1.0 v2.0 webpage Nothing to show v2.11.1 v2.11.0 v2.10.2 v2.10.1 v2.10.0 v2.9.0 v2.8.0 v2.7.0 v2.6.2 v2.6.1 v2.6.0 v2.5.5 v2.5.4 v2.5.3 v2.5.2 v2.5.1 v2.5.0 v2.4.3 v2.4.2 v2.4.1 v2.4.0 v2.3.2 v2.3.1 v2.3.0 v2.2.0 v2.1.1 v2.1.0 v2.0.1 v2.0.0 v2.0.0-rc2 v2.0.0-preview v2.0.0-alpha9 v2.0.0-alpha8 v2.0.0-alpha7 v2.0.0-alpha4 v2.0.0-alpha3 v2.0.0-alpha2 v2.0.0-alpha v0.9.6 v0.9.5 v0.9.4 v0.9.3 v0.9.2 v0.9.1 v0.9.0 v0.8.0 v0.7.0 v0.6.0 v0.5.0 v0.4.0 v0.3.0 v0.2.0 v0.1.0 Nothing to show New pull request Latest commit a0f2cec Oct 7, 2016 dougwilson docs: add documentation about second argument to escapeId … closes #1533 Permalink Failed to load latest commit information. benchmark Fix parser benchmark May 31, 2012 lib Fix typo in HANDSHAKE_NO_SSL_SUPPORT error message Oct 7, 2016 test lint: prefer triple equal operator Sep 29, 2016 tool Add new error codes up to MySQL 5.7.9 Nov 30, 2015 .eslintrc lint: prefer triple equal operator Sep 29, 2016 .gitignore build: clean up .gitignore Mar 22, 2015 .travis.yml build: Node.js@6.6 Sep 26, 2016 Changes.md Fix typo in HANDSHAKE_NO_SSL_SUPPORT error message Oct 7, 2016 License Add License (MIT) May 11, 2012 Readme.md docs: add documentation about second argument to escapeId Oct 7, 2016 appveyor.yml build: Node.js@6.6 Sep 26, 2016 index.js lint: require valid JSDoc comments May 29, 2016 package.json build: eslint@3.6.1 Sep 29, 2016 Readme.md mysql Table of Contents Install Introduction Contributors Sponsors Community Establishing connections Connection options SSL options Terminating connections Pooling connections Pool options Pool events Closing all the connections in a pool PoolCluster PoolCluster options Switching users and altering connection state Server disconnects Performing queries Escaping que