Connect Ruby and MySQL - mysql

Question

trying to connect ruby and mysql. When running a basic script to access the database getting the error:
Unable to load driver 'Mysql' (underlying error: uninitialized constant DBI::DBD::Mysql) (DBI::InterfaceError)
Googled it and found solution:
gem install mysql
gem install dbd-mysql
First one, gives error:
checking for mysql_ssl_set()... yes
checking for rb_str_set_len()... yes
checking for rb_thread_start_timer()... no
checking for mysql.h... yes
creating Makefile
current directory: /home/wheatman/.rvm/gems/ruby-2.7.2/gems/mysql-2.9.1/ext/mysql_api
make "DESTDIR=" clean
current directory: /home/wheatman/.rvm/gems/ruby-2.7.2/gems/mysql-2.9.1/ext/mysql_api
make "DESTDIR="
compiling mysql.c
mysql.c:79:2: error: unknown type name ‘my_bool’
79 | my_bool *is_null;
| ^~~~~~~
mysql.c: In function ‘options’:
mysql.c:361:5: error: unknown type name ‘my_bool’; did you mean ‘bool’?
361 | my_bool b;
| ^~~~~~~
| bool
mysql.c:391:10: error: ‘MYSQL_SET_CLIENT_IP’ undeclared (first use in this function); did you mean ‘MYSQL_SET_CHARSET_DIR’?
391 | case MYSQL_SET_CLIENT_IP:
| ^~~~~~~~~~~~~~~~~~~
| MYSQL_SET_CHARSET_DIR
mysql.c:391:10: note: each undeclared identifier is reported only once for each function it appears in
mysql.c:398:10: error: ‘MYSQL_SECURE_AUTH’ undeclared (first use in this function); did you mean ‘MYSQL_DEFAULT_AUTH’?
398 | case MYSQL_SECURE_AUTH:
| ^~~~~~~~~~~~~~~~~
| MYSQL_DEFAULT_AUTH
mysql.c: In function ‘stmt_init’:
mysql.c:878:5: error: ‘my_bool’ undeclared (first use in this function)
878 | my_bool true = 1;
| ^~~~~~~
mysql.c:878:12: error: expected ‘;’ before numeric constant
878 | my_bool true = 1;
| ^
| ;
mysql.c:883:61: error: lvalue required as unary ‘&’ operand
883 | if (mysql_stmt_attr_set(s, STMT_ATTR_UPDATE_MAX_LENGTH, &true))
| ^
mysql.c: In function ‘stmt_bind_result’:
mysql.c:1320:74: error: ‘rb_cFixnum’ undeclared (first use in this function)
1320 | else if (argv[i] == rb_cNumeric || argv[i] == rb_cInteger || argv[i] == rb_cFixnum)
| ^~~~~~~~~~
mysql.c: In function ‘stmt_prepare’:
mysql.c:1681:32: warning: assignment to ‘_Bool *’ from incompatible pointer type ‘int *’ [-Wincompatible-pointer-types]
1681 | s->result.bind[i].is_null = &(s->result.is_null[i]);
| ^
In file included from /home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby.h:33,
from mysql.c:5:
mysql.c: In function ‘Init_mysql_api’:
mysql.c:2049:52: error: ‘MYSQL_SECURE_AUTH’ undeclared (first use in this function); did you mean ‘MYSQL_DEFAULT_AUTH’?
2049 | rb_define_const(cMysql, "SECURE_AUTH", INT2NUM(MYSQL_SECURE_AUTH));
| ^~~~~~~~~~~~~~~~~
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:262:33: note: in definition of macro ‘RB_INT2FIX’
262 | #define RB_INT2FIX(i) (((VALUE)(i))<<1 | RUBY_FIXNUM_FLAG)
| ^
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:1609:20: note: in expansion of macro ‘RB_INT2NUM’
1609 | #define INT2NUM(x) RB_INT2NUM(x)
| ^~~~~~~~~~
mysql.c:2049:44: note: in expansion of macro ‘INT2NUM’
2049 | rb_define_const(cMysql, "SECURE_AUTH", INT2NUM(MYSQL_SECURE_AUTH));
| ^~~~~~~
mysql.c:2050:61: error: ‘MYSQL_OPT_GUESS_CONNECTION’ undeclared (first use in this function); did you mean ‘MYSQL_OPT_RECONNECT’?
2050 | rb_define_const(cMysql, "OPT_GUESS_CONNECTION", INT2NUM(MYSQL_OPT_GUESS_CONNECTION));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:262:33: note: in definition of macro ‘RB_INT2FIX’
262 | #define RB_INT2FIX(i) (((VALUE)(i))<<1 | RUBY_FIXNUM_FLAG)
| ^
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:1609:20: note: in expansion of macro ‘RB_INT2NUM’
1609 | #define INT2NUM(x) RB_INT2NUM(x)
| ^~~~~~~~~~
mysql.c:2050:53: note: in expansion of macro ‘INT2NUM’
2050 | rb_define_const(cMysql, "OPT_GUESS_CONNECTION", INT2NUM(MYSQL_OPT_GUESS_CONNECTION));
| ^~~~~~~
mysql.c:2051:68: error: ‘MYSQL_OPT_USE_EMBEDDED_CONNECTION’ undeclared (first use in this function)
2051 | rb_define_const(cMysql, "OPT_USE_EMBEDDED_CONNECTION", INT2NUM(MYSQL_OPT_USE_EMBEDDED_CONNECTION));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:262:33: note: in definition of macro ‘RB_INT2FIX’
262 | #define RB_INT2FIX(i) (((VALUE)(i))<<1 | RUBY_FIXNUM_FLAG)
| ^
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:1609:20: note: in expansion of macro ‘RB_INT2NUM’
1609 | #define INT2NUM(x) RB_INT2NUM(x)
| ^~~~~~~~~~
mysql.c:2051:60: note: in expansion of macro ‘INT2NUM’
2051 | rb_define_const(cMysql, "OPT_USE_EMBEDDED_CONNECTION", INT2NUM(MYSQL_OPT_USE_EMBEDDED_CONNECTION));
| ^~~~~~~
mysql.c:2052:66: error: ‘MYSQL_OPT_USE_REMOTE_CONNECTION’ undeclared (first use in this function)
2052 | rb_define_const(cMysql, "OPT_USE_REMOTE_CONNECTION", INT2NUM(MYSQL_OPT_USE_REMOTE_CONNECTION));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:262:33: note: in definition of macro ‘RB_INT2FIX’
262 | #define RB_INT2FIX(i) (((VALUE)(i))<<1 | RUBY_FIXNUM_FLAG)
| ^
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:1609:20: note: in expansion of macro ‘RB_INT2NUM’
1609 | #define INT2NUM(x) RB_INT2NUM(x)
| ^~~~~~~~~~
mysql.c:2052:58: note: in expansion of macro ‘INT2NUM’
2052 | rb_define_const(cMysql, "OPT_USE_REMOTE_CONNECTION", INT2NUM(MYSQL_OPT_USE_REMOTE_CONNECTION));
| ^~~~~~~
mysql.c:2053:54: error: ‘MYSQL_SET_CLIENT_IP’ undeclared (first use in this function); did you mean ‘MYSQL_SET_CHARSET_DIR’?
2053 | rb_define_const(cMysql, "SET_CLIENT_IP", INT2NUM(MYSQL_SET_CLIENT_IP));
| ^~~~~~~~~~~~~~~~~~~
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:262:33: note: in definition of macro ‘RB_INT2FIX’
262 | #define RB_INT2FIX(i) (((VALUE)(i))<<1 | RUBY_FIXNUM_FLAG)
| ^
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:1609:20: note: in expansion of macro ‘RB_INT2NUM’
1609 | #define INT2NUM(x) RB_INT2NUM(x)
| ^~~~~~~~~~
mysql.c:2053:46: note: in expansion of macro ‘INT2NUM’
2053 | rb_define_const(cMysql, "SET_CLIENT_IP", INT2NUM(MYSQL_SET_CLIENT_IP));
| ^~~~~~~
error_const.h:2661:27: error: ‘ER_XPLUGIN_IP’ undeclared (first use in this function); did you mean ‘ER_PLUGIN_OOM’?
2661 | rb_define_mysql_const(ER_XPLUGIN_IP);
| ^~~~~~~~~~~~~
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:262:33: note: in definition of macro ‘RB_INT2FIX’
262 | #define RB_INT2FIX(i) (((VALUE)(i))<<1 | RUBY_FIXNUM_FLAG)
| ^
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:1609:20: note: in expansion of macro ‘RB_INT2NUM’
1609 | #define INT2NUM(x) RB_INT2NUM(x)
| ^~~~~~~~~~
mysql.c:2286:62: note: in expansion of macro ‘INT2NUM’
2286 | #define rb_define_mysql_const(s) rb_define_const(eMysql, #s, INT2NUM(s))
| ^~~~~~~
error_const.h:2661:5: note: in expansion of macro ‘rb_define_mysql_const’
2661 | rb_define_mysql_const(ER_XPLUGIN_IP);
| ^~~~~~~~~~~~~~~~~~~~~
mysql.c: At top level:
cc1: note: unrecognized command-line option ‘-Wno-self-assign’ may have been intended to silence earlier diagnostics
cc1: note: unrecognized command-line option ‘-Wno-parentheses-equality’ may have been intended to silence earlier diagnostics
cc1: note: unrecognized command-line option ‘-Wno-constant-logical-operand’ may have been intended to silence earlier diagnostics
make: *** [Makefile:245: mysql.o] Error 1
make failed, exit code 2
Gem files will remain installed in /home/wheatman/.rvm/gems/ruby-2.7.2/gems/mysql-2.9.1 for inspection.
Results logged to /home/wheatman/.rvm/gems/ruby-2.7.2/extensions/x86_64-linux/2.7.0/mysql-2.9.1/gem_make.out
And the second one gives another error:
Building native extensions. This could take a while...
ERROR: Error installing dbd-mysql:
ERROR: Failed to build gem native extension.
current directory: /home/wheatman/.rvm/gems/ruby-2.7.2/gems/mysql-2.9.1/ext/mysql_api
/home/wheatman/.rvm/rubies/ruby-2.7.2/bin/ruby -I /home/wheatman/.rvm/rubies/ruby-2.7.2/lib/ruby/2.7.0 -r ./siteconf20201219-250830-klyeov.rb extconf.rb
checking for mysql_ssl_set()... yes
checking for rb_str_set_len()... yes
checking for rb_thread_start_timer()... no
checking for mysql.h... yes
creating Makefile
current directory: /home/wheatman/.rvm/gems/ruby-2.7.2/gems/mysql-2.9.1/ext/mysql_api
make "DESTDIR=" clean
current directory: /home/wheatman/.rvm/gems/ruby-2.7.2/gems/mysql-2.9.1/ext/mysql_api
make "DESTDIR="
compiling mysql.c
mysql.c:79:2: error: unknown type name ‘my_bool’
79 | my_bool *is_null;
| ^~~~~~~
mysql.c: In function ‘options’:
mysql.c:361:5: error: unknown type name ‘my_bool’; did you mean ‘bool’?
361 | my_bool b;
| ^~~~~~~
| bool
mysql.c:391:10: error: ‘MYSQL_SET_CLIENT_IP’ undeclared (first use in this function); did you mean ‘MYSQL_SET_CHARSET_DIR’?
391 | case MYSQL_SET_CLIENT_IP:
| ^~~~~~~~~~~~~~~~~~~
| MYSQL_SET_CHARSET_DIR
mysql.c:391:10: note: each undeclared identifier is reported only once for each function it appears in
mysql.c:398:10: error: ‘MYSQL_SECURE_AUTH’ undeclared (first use in this function); did you mean ‘MYSQL_DEFAULT_AUTH’?
398 | case MYSQL_SECURE_AUTH:
| ^~~~~~~~~~~~~~~~~
| MYSQL_DEFAULT_AUTH
mysql.c: In function ‘stmt_init’:
mysql.c:878:5: error: ‘my_bool’ undeclared (first use in this function)
878 | my_bool true = 1;
| ^~~~~~~
mysql.c:878:12: error: expected ‘;’ before numeric constant
878 | my_bool true = 1;
| ^
| ;
mysql.c:883:61: error: lvalue required as unary ‘&’ operand
883 | if (mysql_stmt_attr_set(s, STMT_ATTR_UPDATE_MAX_LENGTH, &true))
| ^
mysql.c: In function ‘stmt_bind_result’:
mysql.c:1320:74: error: ‘rb_cFixnum’ undeclared (first use in this function)
1320 | else if (argv[i] == rb_cNumeric || argv[i] == rb_cInteger || argv[i] == rb_cFixnum)
| ^~~~~~~~~~
mysql.c: In function ‘stmt_prepare’:
mysql.c:1681:32: warning: assignment to ‘_Bool *’ from incompatible pointer type ‘int *’ [-Wincompatible-pointer-types]
1681 | s->result.bind[i].is_null = &(s->result.is_null[i]);
| ^
In file included from /home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby.h:33,
from mysql.c:5:
mysql.c: In function ‘Init_mysql_api’:
mysql.c:2049:52: error: ‘MYSQL_SECURE_AUTH’ undeclared (first use in this function); did you mean ‘MYSQL_DEFAULT_AUTH’?
2049 | rb_define_const(cMysql, "SECURE_AUTH", INT2NUM(MYSQL_SECURE_AUTH));
| ^~~~~~~~~~~~~~~~~
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:262:33: note: in definition of macro ‘RB_INT2FIX’
262 | #define RB_INT2FIX(i) (((VALUE)(i))<<1 | RUBY_FIXNUM_FLAG)
| ^
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:1609:20: note: in expansion of macro ‘RB_INT2NUM’
1609 | #define INT2NUM(x) RB_INT2NUM(x)
| ^~~~~~~~~~
mysql.c:2049:44: note: in expansion of macro ‘INT2NUM’
2049 | rb_define_const(cMysql, "SECURE_AUTH", INT2NUM(MYSQL_SECURE_AUTH));
| ^~~~~~~
mysql.c:2050:61: error: ‘MYSQL_OPT_GUESS_CONNECTION’ undeclared (first use in this function); did you mean ‘MYSQL_OPT_RECONNECT’?
2050 | rb_define_const(cMysql, "OPT_GUESS_CONNECTION", INT2NUM(MYSQL_OPT_GUESS_CONNECTION));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:262:33: note: in definition of macro ‘RB_INT2FIX’
262 | #define RB_INT2FIX(i) (((VALUE)(i))<<1 | RUBY_FIXNUM_FLAG)
| ^
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:1609:20: note: in expansion of macro ‘RB_INT2NUM’
1609 | #define INT2NUM(x) RB_INT2NUM(x)
| ^~~~~~~~~~
mysql.c:2050:53: note: in expansion of macro ‘INT2NUM’
2050 | rb_define_const(cMysql, "OPT_GUESS_CONNECTION", INT2NUM(MYSQL_OPT_GUESS_CONNECTION));
| ^~~~~~~
mysql.c:2051:68: error: ‘MYSQL_OPT_USE_EMBEDDED_CONNECTION’ undeclared (first use in this function)
2051 | rb_define_const(cMysql, "OPT_USE_EMBEDDED_CONNECTION", INT2NUM(MYSQL_OPT_USE_EMBEDDED_CONNECTION));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:262:33: note: in definition of macro ‘RB_INT2FIX’
262 | #define RB_INT2FIX(i) (((VALUE)(i))<<1 | RUBY_FIXNUM_FLAG)
| ^
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:1609:20: note: in expansion of macro ‘RB_INT2NUM’
1609 | #define INT2NUM(x) RB_INT2NUM(x)
| ^~~~~~~~~~
mysql.c:2051:60: note: in expansion of macro ‘INT2NUM’
2051 | rb_define_const(cMysql, "OPT_USE_EMBEDDED_CONNECTION", INT2NUM(MYSQL_OPT_USE_EMBEDDED_CONNECTION));
| ^~~~~~~
mysql.c:2052:66: error: ‘MYSQL_OPT_USE_REMOTE_CONNECTION’ undeclared (first use in this function)
2052 | rb_define_const(cMysql, "OPT_USE_REMOTE_CONNECTION", INT2NUM(MYSQL_OPT_USE_REMOTE_CONNECTION));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:262:33: note: in definition of macro ‘RB_INT2FIX’
262 | #define RB_INT2FIX(i) (((VALUE)(i))<<1 | RUBY_FIXNUM_FLAG)
| ^
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:1609:20: note: in expansion of macro ‘RB_INT2NUM’
1609 | #define INT2NUM(x) RB_INT2NUM(x)
| ^~~~~~~~~~
mysql.c:2052:58: note: in expansion of macro ‘INT2NUM’
2052 | rb_define_const(cMysql, "OPT_USE_REMOTE_CONNECTION", INT2NUM(MYSQL_OPT_USE_REMOTE_CONNECTION));
| ^~~~~~~
mysql.c:2053:54: error: ‘MYSQL_SET_CLIENT_IP’ undeclared (first use in this function); did you mean ‘MYSQL_SET_CHARSET_DIR’?
2053 | rb_define_const(cMysql, "SET_CLIENT_IP", INT2NUM(MYSQL_SET_CLIENT_IP));
| ^~~~~~~~~~~~~~~~~~~
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:262:33: note: in definition of macro ‘RB_INT2FIX’
262 | #define RB_INT2FIX(i) (((VALUE)(i))<<1 | RUBY_FIXNUM_FLAG)
| ^
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:1609:20: note: in expansion of macro ‘RB_INT2NUM’
1609 | #define INT2NUM(x) RB_INT2NUM(x)
| ^~~~~~~~~~
mysql.c:2053:46: note: in expansion of macro ‘INT2NUM’
2053 | rb_define_const(cMysql, "SET_CLIENT_IP", INT2NUM(MYSQL_SET_CLIENT_IP));
| ^~~~~~~
error_const.h:2661:27: error: ‘ER_XPLUGIN_IP’ undeclared (first use in this function); did you mean ‘ER_PLUGIN_OOM’?
2661 | rb_define_mysql_const(ER_XPLUGIN_IP);
| ^~~~~~~~~~~~~
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:262:33: note: in definition of macro ‘RB_INT2FIX’
262 | #define RB_INT2FIX(i) (((VALUE)(i))<<1 | RUBY_FIXNUM_FLAG)
| ^
/home/wheatman/.rvm/rubies/ruby-2.7.2/include/ruby-2.7.0/ruby/ruby.h:1609:20: note: in expansion of macro ‘RB_INT2NUM’
1609 | #define INT2NUM(x) RB_INT2NUM(x)
| ^~~~~~~~~~
mysql.c:2286:62: note: in expansion of macro ‘INT2NUM’
2286 | #define rb_define_mysql_const(s) rb_define_const(eMysql, #s, INT2NUM(s))
| ^~~~~~~
error_const.h:2661:5: note: in expansion of macro ‘rb_define_mysql_const’
2661 | rb_define_mysql_const(ER_XPLUGIN_IP);
| ^~~~~~~~~~~~~~~~~~~~~
mysql.c: At top level:
cc1: note: unrecognized command-line option ‘-Wno-self-assign’ may have been intended to silence earlier diagnostics
cc1: note: unrecognized command-line option ‘-Wno-parentheses-equality’ may have been intended to silence earlier diagnostics
cc1: note: unrecognized command-line option ‘-Wno-constant-logical-operand’ may have been intended to silence earlier diagnostics
make: *** [Makefile:245: mysql.o] Error 1
make failed, exit code 2
Gem files will remain installed in /home/wheatman/.rvm/gems/ruby-2.7.2/gems/mysql-2.9.1 for inspection.
Results logged to /home/wheatman/.rvm/gems/ruby-2.7.2/extensions/x86_64-linux/2.7.0/mysql-2.9.1/gem_make.out
Am using Ubuntu 20.10, ruby 2.7.2 and mysql 8.0.22 and as far as I understand the problem in versions. Have someone encountered such problem? Is it versions issue? Any chance to connect ruby with mysql with my versions or I need to go back to older ones?

Answer 1

You're using extremely outdated and abandoned tools. The mysql gem has not seen a new release since 2013 and dbd-mysql has not been updated since 2010. Its highly questionable if they will work with modern versions of Ruby and MySQL.
What you want is the the mysql2 gem which is actively maintained.
# https://bundler.io/guides/bundler_in_a_single_file_ruby_script.html
require 'bundler/inline'
gemfile do
source 'https://rubygems.org'
gem 'mysql2', '~> 0.5.2'
end
client = Mysql2::Client.new(host: "localhost", username: "root")
results = client.query("SELECT * FROM users")
results.each do |row|
# do something with row, it's ready to rock
end