mysql 中COMMANDS 支持的所有命令

本文介绍了一种用于解析MySQL命令的数据结构,详细解释了每个命令的功能及其使用方式。通过定义COMMANDS结构体,文章列举了一系列MySQL客户端命令,如帮助、清除、连接等,并提供了这些命令的简要说明。

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typedef struct {
  const char *name; /* User printable name of the function. */
  char cmd_char; /* msql command character */
  int (*func)(String *str,char *); /* Function to call to do the job. */
  bool takes_params; /* Max parameters for command */
  const char *doc; /* Documentation for this function.  */

} COMMANDS;


名字

简写

函数地址

是否接收参数

简介



static COMMANDS commands[] = {
  { "?",      '?', com_help,   1, "Synonym for `help'." },
  { "clear",  'c', com_clear,  0, "Clear the current input statement."},
  { "connect",'r', com_connect,1,
    "Reconnect to the server. Optional arguments are db and host." },
  { "delimiter", 'd', com_delimiter,    1,
    "Set statement delimiter." },
#ifdef USE_POPEN
  { "edit",   'e', com_edit,   0, "Edit command with $EDITOR."},
#endif
  { "ego",    'G', com_ego,    0,
    "Send command to mysql server, display result vertically."},
  { "exit",   'q', com_quit,   0, "Exit mysql. Same as quit."},
  { "go",     'g', com_go,     0, "Send command to mysql server." },
  { "help",   'h', com_help,   1, "Display this help." },
#ifdef USE_POPEN
  { "nopager",'n', com_nopager,0, "Disable pager, print to stdout." },
#endif
  { "notee",  't', com_notee,  0, "Don't write into outfile." },
#ifdef USE_POPEN
  { "pager",  'P', com_pager,  1, 
    "Set PAGER [to_pager]. Print the query results via PAGER." },
#endif
  { "print",  'p', com_print,  0, "Print current command." },
  { "prompt", 'R', com_prompt, 1, "Change your mysql prompt."},
  { "quit",   'q', com_quit,   0, "Quit mysql." },
  { "rehash", '#', com_rehash, 0, "Rebuild completion hash." },
  { "source", '.', com_source, 1,
    "Execute an SQL script file. Takes a file name as an argument."},
  { "status", 's', com_status, 0, "Get status information from the server."},
#ifdef USE_POPEN
  { "system", '!', com_shell,  1, "Execute a system shell command."},
#endif
  { "tee",    'T', com_tee,    1, 
    "Set outfile [to_outfile]. Append everything into given outfile." },
  { "use",    'u', com_use,    1,
    "Use another database. Takes database name as argument." },
  { "charset",    'C', com_charset,    1,
    "Switch to another charset. Might be needed for processing binlog with multi-byte charsets." },
  { "warnings", 'W', com_warnings,  0,
    "Show warnings after every statement." },
  { "nowarning", 'w', com_nowarnings, 0,
    "Don't show warnings after every statement." },
  /* Get bash-like expansion for some commands */
  { "create table",     0, 0, 0, ""},
  { "create database",  0, 0, 0, ""},
  { "show databases",   0, 0, 0, ""},
  { "show fields from", 0, 0, 0, ""},
  { "show keys from",   0, 0, 0, ""},
  { "show tables",      0, 0, 0, ""},
  { "load data from",   0, 0, 0, ""},
  { "alter table",      0, 0, 0, ""},
  { "set option",       0, 0, 0, ""},
  { "lock tables",      0, 0, 0, ""},
  { "unlock tables",    0, 0, 0, ""},
  /* generated 2006-12-28.  Refresh occasionally from lexer. */
  { "ACTION", 0, 0, 0, ""},
  { "ADD", 0, 0, 0, ""},
  { "AFTER", 0, 0, 0, ""},
  { "AGAINST", 0, 0, 0, ""},
  { "AGGREGATE", 0, 0, 0, ""},
  { "ALL", 0, 0, 0, ""},
  { "ALGORITHM", 0, 0, 0, ""},
  { "ALTER", 0, 0, 0, ""},
  { "ANALYZE", 0, 0, 0, ""},
  { "AND", 0, 0, 0, ""},
  { "ANY", 0, 0, 0, ""},
  { "AS", 0, 0, 0, ""},
  { "ASC", 0, 0, 0, ""},
  { "ASCII", 0, 0, 0, ""},
  { "ASENSITIVE", 0, 0, 0, ""},
  { "AUTO_INCREMENT", 0, 0, 0, ""},
  { "AVG", 0, 0, 0, ""},
  { "AVG_ROW_LENGTH", 0, 0, 0, ""},
  { "BACKUP", 0, 0, 0, ""},
  { "BDB", 0, 0, 0, ""},
  { "BEFORE", 0, 0, 0, ""},
  { "BEGIN", 0, 0, 0, ""},
  { "BERKELEYDB", 0, 0, 0, ""},
  { "BETWEEN", 0, 0, 0, ""},
  { "BIGINT", 0, 0, 0, ""},
  { "BINARY", 0, 0, 0, ""},
  { "BINLOG", 0, 0, 0, ""},
  { "BIT", 0, 0, 0, ""},
  { "BLOB", 0, 0, 0, ""},
  { "BOOL", 0, 0, 0, ""},
  { "BOOLEAN", 0, 0, 0, ""},
  { "BOTH", 0, 0, 0, ""},
  { "BTREE", 0, 0, 0, ""},
  { "BY", 0, 0, 0, ""},
  { "BYTE", 0, 0, 0, ""},
  { "CACHE", 0, 0, 0, ""},
  { "CALL", 0, 0, 0, ""},
  { "CASCADE", 0, 0, 0, ""},
  { "CASCADED", 0, 0, 0, ""},
  { "CASE", 0, 0, 0, ""},
  { "CHAIN", 0, 0, 0, ""},
  { "CHANGE", 0, 0, 0, ""},
  { "CHANGED", 0, 0, 0, ""},
  { "CHAR", 0, 0, 0, ""},
  { "CHARACTER", 0, 0, 0, ""},
  { "CHARSET", 0, 0, 0, ""},
  { "CHECK", 0, 0, 0, ""},
  { "CHECKSUM", 0, 0, 0, ""},
  { "CIPHER", 0, 0, 0, ""},
  { "CLIENT", 0, 0, 0, ""},
  { "CLOSE", 0, 0, 0, ""},
  { "CODE", 0, 0, 0, ""},
  { "COLLATE", 0, 0, 0, ""},
  { "COLLATION", 0, 0, 0, ""},
  { "COLUMN", 0, 0, 0, ""},
  { "COLUMNS", 0, 0, 0, ""},
  { "COMMENT", 0, 0, 0, ""},
  { "COMMIT", 0, 0, 0, ""},
  { "COMMITTED", 0, 0, 0, ""},
  { "COMPACT", 0, 0, 0, ""},
  { "COMPRESSED", 0, 0, 0, ""},
  { "CONCURRENT", 0, 0, 0, ""},
  { "CONDITION", 0, 0, 0, ""},
  { "CONNECTION", 0, 0, 0, ""},
  { "CONSISTENT", 0, 0, 0, ""},
  { "CONSTRAINT", 0, 0, 0, ""},
  { "CONTAINS", 0, 0, 0, ""},
  { "CONTINUE", 0, 0, 0, ""},
  { "CONVERT", 0, 0, 0, ""},
  { "CREATE", 0, 0, 0, ""},
  { "CROSS", 0, 0, 0, ""},
  { "CUBE", 0, 0, 0, ""},
  { "CURRENT_DATE", 0, 0, 0, ""},
  { "CURRENT_TIME", 0, 0, 0, ""},
  { "CURRENT_TIMESTAMP", 0, 0, 0, ""},
  { "CURRENT_USER", 0, 0, 0, ""},
  { "CURSOR", 0, 0, 0, ""},
  { "DATA", 0, 0, 0, ""},
  { "DATABASE", 0, 0, 0, ""},
  { "DATABASES", 0, 0, 0, ""},
  { "DATE", 0, 0, 0, ""},
  { "DATETIME", 0, 0, 0, ""},
  { "DAY", 0, 0, 0, ""},
  { "DAY_HOUR", 0, 0, 0, ""},
  { "DAY_MICROSECOND", 0, 0, 0, ""},
  { "DAY_MINUTE", 0, 0, 0, ""},
  { "DAY_SECOND", 0, 0, 0, ""},
  { "DEALLOCATE", 0, 0, 0, ""},     
  { "DEC", 0, 0, 0, ""},
  { "DECIMAL", 0, 0, 0, ""},
  { "DECLARE", 0, 0, 0, ""},
  { "DEFAULT", 0, 0, 0, ""},
  { "DEFINER", 0, 0, 0, ""},
  { "DELAYED", 0, 0, 0, ""},
  { "DELAY_KEY_WRITE", 0, 0, 0, ""},
  { "DELETE", 0, 0, 0, ""},
  { "DESC", 0, 0, 0, ""},
  { "DESCRIBE", 0, 0, 0, ""},
  { "DES_KEY_FILE", 0, 0, 0, ""},
  { "DETERMINISTIC", 0, 0, 0, ""},
  { "DIRECTORY", 0, 0, 0, ""},
  { "DISABLE", 0, 0, 0, ""},
  { "DISCARD", 0, 0, 0, ""},
  { "DISTINCT", 0, 0, 0, ""},
  { "DISTINCTROW", 0, 0, 0, ""},
  { "DIV", 0, 0, 0, ""},
  { "DO", 0, 0, 0, ""},
  { "DOUBLE", 0, 0, 0, ""},
  { "DROP", 0, 0, 0, ""},
  { "DUAL", 0, 0, 0, ""},
  { "DUMPFILE", 0, 0, 0, ""},
  { "DUPLICATE", 0, 0, 0, ""},
  { "DYNAMIC", 0, 0, 0, ""},
  { "EACH", 0, 0, 0, ""},
  { "ELSE", 0, 0, 0, ""},
  { "ELSEIF", 0, 0, 0, ""},
  { "ENABLE", 0, 0, 0, ""},
  { "ENCLOSED", 0, 0, 0, ""},
  { "END", 0, 0, 0, ""},
  { "ENGINE", 0, 0, 0, ""},
  { "ENGINES", 0, 0, 0, ""},
  { "ENUM", 0, 0, 0, ""},
  { "ERRORS", 0, 0, 0, ""},
  { "ESCAPE", 0, 0, 0, ""},
  { "ESCAPED", 0, 0, 0, ""},
  { "EVENTS", 0, 0, 0, ""},
  { "EXECUTE", 0, 0, 0, ""},
  { "EXISTS", 0, 0, 0, ""},
  { "EXIT", 0, 0, 0, ""},
  { "EXPANSION", 0, 0, 0, ""},
  { "EXPLAIN", 0, 0, 0, ""},
  { "EXTENDED", 0, 0, 0, ""},
  { "FALSE", 0, 0, 0, ""},
  { "FAST", 0, 0, 0, ""},
  { "FETCH", 0, 0, 0, ""},
  { "FIELDS", 0, 0, 0, ""},
  { "FILE", 0, 0, 0, ""},
  { "FIRST", 0, 0, 0, ""},
  { "FIXED", 0, 0, 0, ""},
  { "FLOAT", 0, 0, 0, ""},
  { "FLOAT4", 0, 0, 0, ""},
  { "FLOAT8", 0, 0, 0, ""},
  { "FLUSH", 0, 0, 0, ""},
  { "FOR", 0, 0, 0, ""},
  { "FORCE", 0, 0, 0, ""},
  { "FOREIGN", 0, 0, 0, ""},
  { "FOUND", 0, 0, 0, ""},
  { "FRAC_SECOND", 0, 0, 0, ""},
  { "FROM", 0, 0, 0, ""},
  { "FULL", 0, 0, 0, ""},
  { "FULLTEXT", 0, 0, 0, ""},
  { "FUNCTION", 0, 0, 0, ""},
  { "GEOMETRY", 0, 0, 0, ""},
  { "GEOMETRYCOLLECTION", 0, 0, 0, ""},
  { "GET_FORMAT", 0, 0, 0, ""},
  { "GLOBAL", 0, 0, 0, ""},
  { "GRANT", 0, 0, 0, ""},
  { "GRANTS", 0, 0, 0, ""},
  { "GROUP", 0, 0, 0, ""},
  { "HANDLER", 0, 0, 0, ""},
  { "HASH", 0, 0, 0, ""},
  { "HAVING", 0, 0, 0, ""},
  { "HELP", 0, 0, 0, ""},
  { "HIGH_PRIORITY", 0, 0, 0, ""},
  { "HOSTS", 0, 0, 0, ""},
  { "HOUR", 0, 0, 0, ""},
  { "HOUR_MICROSECOND", 0, 0, 0, ""},
  { "HOUR_MINUTE", 0, 0, 0, ""},
  { "HOUR_SECOND", 0, 0, 0, ""},
  { "IDENTIFIED", 0, 0, 0, ""},
  { "IF", 0, 0, 0, ""},
  { "IGNORE", 0, 0, 0, ""},
  { "IMPORT", 0, 0, 0, ""},
  { "IN", 0, 0, 0, ""},
  { "INDEX", 0, 0, 0, ""},
  { "INDEXES", 0, 0, 0, ""},
  { "INFILE", 0, 0, 0, ""},
  { "INNER", 0, 0, 0, ""},
  { "INNOBASE", 0, 0, 0, ""},
  { "INNODB", 0, 0, 0, ""},
  { "INOUT", 0, 0, 0, ""},
  { "INSENSITIVE", 0, 0, 0, ""},
  { "INSERT", 0, 0, 0, ""},
  { "INSERT_METHOD", 0, 0, 0, ""},
  { "INT", 0, 0, 0, ""},
  { "INT1", 0, 0, 0, ""},
  { "INT2", 0, 0, 0, ""},
  { "INT3", 0, 0, 0, ""},
  { "INT4", 0, 0, 0, ""},
  { "INT8", 0, 0, 0, ""},
  { "INTEGER", 0, 0, 0, ""},
  { "INTERVAL", 0, 0, 0, ""},
  { "INTO", 0, 0, 0, ""},
  { "IO_THREAD", 0, 0, 0, ""},
  { "IS", 0, 0, 0, ""},
  { "ISOLATION", 0, 0, 0, ""},
  { "ISSUER", 0, 0, 0, ""},
  { "ITERATE", 0, 0, 0, ""},
  { "INVOKER", 0, 0, 0, ""},
  { "JOIN", 0, 0, 0, ""},
  { "KEY", 0, 0, 0, ""},
  { "KEYS", 0, 0, 0, ""},
  { "KILL", 0, 0, 0, ""},
  { "LANGUAGE", 0, 0, 0, ""},
  { "LAST", 0, 0, 0, ""},
  { "LEADING", 0, 0, 0, ""},
  { "LEAVE", 0, 0, 0, ""},
  { "LEAVES", 0, 0, 0, ""},
  { "LEFT", 0, 0, 0, ""},
  { "LEVEL", 0, 0, 0, ""},
  { "LIKE", 0, 0, 0, ""},
  { "LIMIT", 0, 0, 0, ""},
  { "LINES", 0, 0, 0, ""},
  { "LINESTRING", 0, 0, 0, ""},
  { "LOAD", 0, 0, 0, ""},
  { "LOCAL", 0, 0, 0, ""},
  { "LOCALTIME", 0, 0, 0, ""},
  { "LOCALTIMESTAMP", 0, 0, 0, ""},
  { "LOCK", 0, 0, 0, ""},
  { "LOCKS", 0, 0, 0, ""},
  { "LOGS", 0, 0, 0, ""},
  { "LONG", 0, 0, 0, ""},
  { "LONGBLOB", 0, 0, 0, ""},
  { "LONGTEXT", 0, 0, 0, ""},
  { "LOOP", 0, 0, 0, ""},
  { "LOW_PRIORITY", 0, 0, 0, ""},
  { "MASTER", 0, 0, 0, ""},
  { "MASTER_CONNECT_RETRY", 0, 0, 0, ""},
  { "MASTER_HOST", 0, 0, 0, ""},
  { "MASTER_LOG_FILE", 0, 0, 0, ""},
  { "MASTER_LOG_POS", 0, 0, 0, ""},
  { "MASTER_PASSWORD", 0, 0, 0, ""},
  { "MASTER_PORT", 0, 0, 0, ""},
  { "MASTER_SERVER_ID", 0, 0, 0, ""},
  { "MASTER_SSL", 0, 0, 0, ""},
  { "MASTER_SSL_CA", 0, 0, 0, ""},
  { "MASTER_SSL_CAPATH", 0, 0, 0, ""},
  { "MASTER_SSL_CERT", 0, 0, 0, ""},
  { "MASTER_SSL_CIPHER", 0, 0, 0, ""},
  { "MASTER_SSL_KEY", 0, 0, 0, ""},
  { "MASTER_USER", 0, 0, 0, ""},
  { "MATCH", 0, 0, 0, ""},
  { "MAX_CONNECTIONS_PER_HOUR", 0, 0, 0, ""},
  { "MAX_QUERIES_PER_HOUR", 0, 0, 0, ""},
  { "MAX_ROWS", 0, 0, 0, ""},
  { "MAX_UPDATES_PER_HOUR", 0, 0, 0, ""},
  { "MAX_USER_CONNECTIONS", 0, 0, 0, ""},
  { "MEDIUM", 0, 0, 0, ""},
  { "MEDIUMBLOB", 0, 0, 0, ""},
  { "MEDIUMINT", 0, 0, 0, ""},
  { "MEDIUMTEXT", 0, 0, 0, ""},
  { "MERGE", 0, 0, 0, ""},
  { "MICROSECOND", 0, 0, 0, ""},
  { "MIDDLEINT", 0, 0, 0, ""},
  { "MIGRATE", 0, 0, 0, ""},
  { "MINUTE", 0, 0, 0, ""},
  { "MINUTE_MICROSECOND", 0, 0, 0, ""},
  { "MINUTE_SECOND", 0, 0, 0, ""},
  { "MIN_ROWS", 0, 0, 0, ""},
  { "MOD", 0, 0, 0, ""},
  { "MODE", 0, 0, 0, ""},
  { "MODIFIES", 0, 0, 0, ""},
  { "MODIFY", 0, 0, 0, ""},
  { "MONTH", 0, 0, 0, ""},
  { "MULTILINESTRING", 0, 0, 0, ""},
  { "MULTIPOINT", 0, 0, 0, ""},
  { "MULTIPOLYGON", 0, 0, 0, ""},
  { "MUTEX", 0, 0, 0, ""},
  { "NAME", 0, 0, 0, ""},
  { "NAMES", 0, 0, 0, ""},
  { "NATIONAL", 0, 0, 0, ""},
  { "NATURAL", 0, 0, 0, ""},
  { "NDB", 0, 0, 0, ""},
  { "NDBCLUSTER", 0, 0, 0, ""},
  { "NCHAR", 0, 0, 0, ""},
  { "NEW", 0, 0, 0, ""},
  { "NEXT", 0, 0, 0, ""},
  { "NO", 0, 0, 0, ""},
  { "NONE", 0, 0, 0, ""},
  { "NOT", 0, 0, 0, ""},
  { "NO_WRITE_TO_BINLOG", 0, 0, 0, ""},
  { "NULL", 0, 0, 0, ""},
  { "NUMERIC", 0, 0, 0, ""},
  { "NVARCHAR", 0, 0, 0, ""},
  { "OFFSET", 0, 0, 0, ""},
  { "OLD_PASSWORD", 0, 0, 0, ""},
  { "ON", 0, 0, 0, ""},
  { "ONE", 0, 0, 0, ""},
  { "ONE_SHOT", 0, 0, 0, ""},
  { "OPEN", 0, 0, 0, ""},
  { "OPTIMIZE", 0, 0, 0, ""},
  { "OPTION", 0, 0, 0, ""},
  { "OPTIONALLY", 0, 0, 0, ""},
  { "OR", 0, 0, 0, ""},
  { "ORDER", 0, 0, 0, ""},
  { "OUT", 0, 0, 0, ""},
  { "OUTER", 0, 0, 0, ""},
  { "OUTFILE", 0, 0, 0, ""},
  { "PACK_KEYS", 0, 0, 0, ""},
  { "PARTIAL", 0, 0, 0, ""},
  { "PASSWORD", 0, 0, 0, ""},
  { "PHASE", 0, 0, 0, ""},
  { "POINT", 0, 0, 0, ""},
  { "POLYGON", 0, 0, 0, ""},
  { "PRECISION", 0, 0, 0, ""},
  { "PREPARE", 0, 0, 0, ""},
  { "PREV", 0, 0, 0, ""},
  { "PRIMARY", 0, 0, 0, ""},
  { "PRIVILEGES", 0, 0, 0, ""},
  { "PROCEDURE", 0, 0, 0, ""},
  { "PROCESS", 0, 0, 0, ""},
  { "PROCESSLIST", 0, 0, 0, ""},
  { "PURGE", 0, 0, 0, ""},
  { "QUARTER", 0, 0, 0, ""},
  { "QUERY", 0, 0, 0, ""},
  { "QUICK", 0, 0, 0, ""},
  { "RAID0", 0, 0, 0, ""},
  { "RAID_CHUNKS", 0, 0, 0, ""},
  { "RAID_CHUNKSIZE", 0, 0, 0, ""},
  { "RAID_TYPE", 0, 0, 0, ""},
  { "READ", 0, 0, 0, ""},
  { "READS", 0, 0, 0, ""},
  { "REAL", 0, 0, 0, ""},
  { "RECOVER", 0, 0, 0, ""},
  { "REDUNDANT", 0, 0, 0, ""},
  { "REFERENCES", 0, 0, 0, ""},
  { "REGEXP", 0, 0, 0, ""},
  { "RELAY_LOG_FILE", 0, 0, 0, ""},
  { "RELAY_LOG_POS", 0, 0, 0, ""},
  { "RELAY_THREAD", 0, 0, 0, ""},
  { "RELEASE", 0, 0, 0, ""},
  { "RELOAD", 0, 0, 0, ""},
  { "RENAME", 0, 0, 0, ""},
  { "REPAIR", 0, 0, 0, ""},
  { "REPEATABLE", 0, 0, 0, ""},
  { "REPLACE", 0, 0, 0, ""},
  { "REPLICATION", 0, 0, 0, ""},
  { "REPEAT", 0, 0, 0, ""},
  { "REQUIRE", 0, 0, 0, ""},
  { "RESET", 0, 0, 0, ""},
  { "RESTORE", 0, 0, 0, ""},
  { "RESTRICT", 0, 0, 0, ""},
  { "RESUME", 0, 0, 0, ""},
  { "RETURN", 0, 0, 0, ""},
  { "RETURNS", 0, 0, 0, ""},
  { "REVOKE", 0, 0, 0, ""},
  { "RIGHT", 0, 0, 0, ""},
  { "RLIKE", 0, 0, 0, ""},
  { "ROLLBACK", 0, 0, 0, ""},
  { "ROLLUP", 0, 0, 0, ""},
  { "ROUTINE", 0, 0, 0, ""},
  { "ROW", 0, 0, 0, ""},
  { "ROWS", 0, 0, 0, ""},
  { "ROW_FORMAT", 0, 0, 0, ""},
  { "RTREE", 0, 0, 0, ""},
  { "SAVEPOINT", 0, 0, 0, ""},
  { "SCHEMA", 0, 0, 0, ""},
  { "SCHEMAS", 0, 0, 0, ""},
  { "SECOND", 0, 0, 0, ""},
  { "SECOND_MICROSECOND", 0, 0, 0, ""},
  { "SECURITY", 0, 0, 0, ""},
  { "SELECT", 0, 0, 0, ""},
  { "SENSITIVE", 0, 0, 0, ""},
  { "SEPARATOR", 0, 0, 0, ""},
  { "SERIAL", 0, 0, 0, ""},
  { "SERIALIZABLE", 0, 0, 0, ""},
  { "SESSION", 0, 0, 0, ""},
  { "SET", 0, 0, 0, ""},
  { "SHARE", 0, 0, 0, ""},
  { "SHOW", 0, 0, 0, ""},
  { "SHUTDOWN", 0, 0, 0, ""},
  { "SIGNED", 0, 0, 0, ""},
  { "SIMPLE", 0, 0, 0, ""},
  { "SLAVE", 0, 0, 0, ""},
  { "SNAPSHOT", 0, 0, 0, ""},
  { "SMALLINT", 0, 0, 0, ""},
  { "SOME", 0, 0, 0, ""},
  { "SONAME", 0, 0, 0, ""},
  { "SOUNDS", 0, 0, 0, ""},
  { "SPATIAL", 0, 0, 0, ""},
  { "SPECIFIC", 0, 0, 0, ""},
  { "SQL", 0, 0, 0, ""},
  { "SQLEXCEPTION", 0, 0, 0, ""},
  { "SQLSTATE", 0, 0, 0, ""},
  { "SQLWARNING", 0, 0, 0, ""},
  { "SQL_BIG_RESULT", 0, 0, 0, ""},
  { "SQL_BUFFER_RESULT", 0, 0, 0, ""},
  { "SQL_CACHE", 0, 0, 0, ""},
  { "SQL_CALC_FOUND_ROWS", 0, 0, 0, ""},
  { "SQL_NO_CACHE", 0, 0, 0, ""},
  { "SQL_SMALL_RESULT", 0, 0, 0, ""},
  { "SQL_THREAD", 0, 0, 0, ""},
  { "SQL_TSI_FRAC_SECOND", 0, 0, 0, ""},
  { "SQL_TSI_SECOND", 0, 0, 0, ""},
  { "SQL_TSI_MINUTE", 0, 0, 0, ""},
  { "SQL_TSI_HOUR", 0, 0, 0, ""},
  { "SQL_TSI_DAY", 0, 0, 0, ""},
  { "SQL_TSI_WEEK", 0, 0, 0, ""},
  { "SQL_TSI_MONTH", 0, 0, 0, ""},
  { "SQL_TSI_QUARTER", 0, 0, 0, ""},
  { "SQL_TSI_YEAR", 0, 0, 0, ""},
  { "SSL", 0, 0, 0, ""},
  { "START", 0, 0, 0, ""},
  { "STARTING", 0, 0, 0, ""},
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  { (char *)NULL,       0, 0, 0, ""}
};

<think>我们正在处理用户关于MySQL查看锁表状态和解锁表的问题。根据引用内容,我们可以总结如下:1.查看锁表状态:-使用`SHOWPROCESSLIST;`或`SHOWFULLPROCESSLIST;`查看当前所有会话。-查询`information_schema.PROCESSLIST`表:`SELECT*FROMinformation_schema.PROCESSLIST;`-查询`information_schema.innodb_trx`表(只显示InnoDB事务):`SELECT*FROMinformation_schema.innodb_trx;`-查询`information_schema.innodb_locks`表(显示InnoDB锁信息):`SELECT*FROMinformation_schema.innodb_locks;`-查询处于锁等待的事务:`SELECT*FROMinformation_schema.innodb_trxWHEREtrx_state='LOCKWAIT';`2.解锁表:-使用`UNLOCKTABLES;`命令可以释放当前会话持有的所有表锁(显式锁表后的解锁)。-对于其他会话(比如长时间等待锁的事务),可以通过杀死会话来解锁。首先找出锁定的进程ID,然后使用`KILL<process_id>;`命令杀死进程。-批量生成杀死进程的语句:`SELECTCONCAT('KILL',id,';')FROMinformation_schema.processlistWHERE...INTOOUTFILE'/tmp/a.txt';`然后执行该文件中的语句(需要文件写入权限)。注意:用户提到的显式锁表(LOCKTABLES)和解锁(UNLOCKTABLES)是针对当前会话的。而通过查询进程并杀死进程的方式可以解除其他会话的锁(包括隐式锁,如事务未提交导致的锁)。但是,用户的问题是如何查看锁表状态和解锁表。这里需要区分:-显式锁表:用户使用`LOCKTABLES...READ/WRITE`命令锁定的表。-隐式锁表:通常是由事务引起的,比如在事务中执行更新操作而没有提交,这时会持有锁。对于隐式锁(InnoDB行锁等),我们通常通过查询`information_schema.innodb_trx`和`information_schema.innodb_locks`等表来查看。因此,回答应该包括:-查看当前所有会话(进程)和锁信息的方法。-如何解锁(显式解锁和杀死进程)。注意:在MySQL5.5及以上版本,`information_schema.innodb_locks`表在MySQL8.0中已被移除,替代的是`performance_schema.data_locks`和`performance_schema.data_lock_waits`。但用户提供的引用中未提及版本,所以我们以用户提供的引用内容为主(引用中提到了`innodb_trx`和`innodb_locks`)。另外,用户引用[3]中提到了通过查询`information_schema.PROCESSLIST`来获取需要杀死的进程ID。步骤总结:一、查看锁表状态:1.使用`SHOWPROCESSLIST;`或`SHOWFULLPROCESSLIST;`查看当前进程,观察是否有长时间处于“Waitingfortablelock”或其他锁等待状态的进程。2.查询事务表:`SELECT*FROMinformation_schema.innodb_trx;`查看当前运行的事务,其中`trx_state`为'LOCKWAIT'的表示正在等待锁。3.查看锁信息(如果存在`innodb_locks`表):`SELECT*FROMinformation_schema.innodb_locks;`可以查看锁的详细信息。二、解锁:1.对于显式锁表(当前会话),使用`UNLOCKTABLES;`解锁。2.对于其他会话导致的锁(可能是未提交事务或显式锁表未释放),可以通过杀死会话来解锁:-首先找到阻塞的进程ID(例如,从`information_schema.processlist`或`innodb_trx`表中找到)。-然后执行`KILL<id>;`命令。另外,引用[4]提到了一种批量生成KILL语句的方法,适用于有多个需要杀死的会话。注意:杀死会话需要谨慎,确保不会影响重要操作。下面根据以上总结给出回答。</think>### MySQL 查看锁表状态与解锁表命令 #### 一、查看锁表状态 1. **当前会话进程列表** ```sql SHOW PROCESSLIST; -- 基础进程信息 SHOW FULL PROCESSLIST; -- 完整进程信息(含操作语句) ``` - 关键列:`State` 列显示 `Waiting for table lock` 表示表锁等待 - 示例输出: ``` Id | User | Host | db | Command | Time | State | Info 6924 | root | localhost | test | Query | 50 | Waiting for table lock | SELECT * FROM orders ``` 2. **事务与锁详细信息** ```sql -- 查看InnoDB事务(含锁状态) SELECT * FROM information_schema.INNODB_TRX; -- 查看当前锁信息(MySQL 5.7及以下) SELECT * FROM information_schema.INNODB_LOCKS; -- 查看锁等待关系(MySQL 5.7及以下) SELECT * FROM information_schema.INNODB_LOCK_WAITS; -- MySQL 8.0+ 使用新表 SELECT * FROM performance_schema.DATA_LOCKS; -- 当前持有锁 SELECT * FROM performance_schema.DATA_LOCK_WAITS; -- 锁等待 ``` - 关键字段: - `trx_state`: `LOCK WAIT` 表示锁等待 - `lock_table`: 被锁定的表名 - `blocking_trx_id`: 阻塞事务的ID #### 二、解锁表操作 1. **释放显式表锁(当前会话)** ```sql UNLOCK TABLES; -- 释放当前会话所有表锁 ``` 2. **终止阻塞进程(强制解锁)** ```sql -- 先查询阻塞进程ID SELECT * FROM information_schema.PROCESSLIST WHERE STATE LIKE '%lock%' AND TIME > 60; -- 筛选长时锁进程 -- 终止进程(需SUPER权限) KILL 6924; -- 6924为阻塞进程ID -- 批量生成KILL语句 SELECT CONCAT('KILL ', id, ';') FROM information_schema.PROCESSLIST WHERE STATE = 'Waiting for table lock' INTO OUTFILE '/tmp/kill_commands.sql'; -- 导出脚本后执行 ``` #### 三、关键注意事项 1. **显式锁表规则** - 使用 `LOCK TABLES table_name READ/WRITE` 后: - 读锁:当前会话仅能查询,其他会话查询会阻塞更新[^2] - 写锁:其他会话读写均阻塞[^1] - 必须显式解锁或会话终止才释放锁 2. **隐式锁(事务)** - 未提交的事务会持有行锁/表锁,需提交或回滚: ```sql COMMIT; -- 提交事务释放锁 ROLLBACK; -- 回滚事务释放锁 ``` 3. **锁升级限制** MySQL支持锁升级(如行锁升级为表锁),需手动管理锁粒度[^1]。 ---
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