Class: Mysql2::Client

Inherits:
Object
  • Object
show all
Defined in:
lib/mysql2/client.rb,
ext/mysql2/client.c

Direct Known Subclasses

EM::Client

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(opts = {}) ⇒ Client

Returns a new instance of Client.



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# File 'lib/mysql2/client.rb', line 21

def initialize(opts = {})
  fail Mysql2::Error, "Options parameter must be a Hash" unless opts.is_a? Hash
  opts = Mysql2::Util.key_hash_as_symbols(opts)
  @read_timeout = nil
  @query_options = self.class.default_query_options.dup
  @query_options.merge! opts

  initialize_ext

  # Set default connect_timeout to avoid unlimited retries from signal interruption
  opts[:connect_timeout] = 120 unless opts.key?(:connect_timeout)

  # TODO: stricter validation rather than silent massaging
  [:reconnect, :connect_timeout, :local_infile, :read_timeout, :write_timeout, :default_file, :default_group, :secure_auth, :init_command, :automatic_close, :enable_cleartext_plugin].each do |key|
    next unless opts.key?(key)
    case key
    when :reconnect, :local_infile, :secure_auth, :automatic_close, :enable_cleartext_plugin
      send(:"#{key}=", !!opts[key]) # rubocop:disable Style/DoubleNegation
    when :connect_timeout, :read_timeout, :write_timeout
      send(:"#{key}=", Integer(opts[key])) unless opts[key].nil?
    else
      send(:"#{key}=", opts[key])
    end
  end

  # force the encoding to utf8
  self.charset_name = opts[:encoding] || 'utf8'

  ssl_options = opts.values_at(:sslkey, :sslcert, :sslca, :sslcapath, :sslcipher)
  ssl_set(*ssl_options) if ssl_options.any?
  self.ssl_mode = parse_ssl_mode(opts[:ssl_mode]) if opts[:ssl_mode]

  case opts[:flags]
  when Array
    flags = parse_flags_array(opts[:flags], @query_options[:connect_flags])
  when String
    flags = parse_flags_array(opts[:flags].split(' '), @query_options[:connect_flags])
  when Integer
    flags = @query_options[:connect_flags] | opts[:flags]
  else
    flags = @query_options[:connect_flags]
  end

  # SSL verify is a connection flag rather than a mysql_ssl_set option
  flags |= SSL_VERIFY_SERVER_CERT if opts[:sslverify] && ssl_options.any?

  if [:user, :pass, :hostname, :dbname, :db, :sock].any? { |k| @query_options.key?(k) }
    warn "============= WARNING FROM mysql2 ============="
    warn "The options :user, :pass, :hostname, :dbname, :db, and :sock are deprecated and will be removed at some point in the future."
    warn "Instead, please use :username, :password, :host, :port, :database, :socket, :flags for the options."
    warn "============= END WARNING FROM mysql2 ========="
  end

  user     = opts[:username] || opts[:user]
  pass     = opts[:password] || opts[:pass]
  host     = opts[:host] || opts[:hostname]
  port     = opts[:port]
  database = opts[:database] || opts[:dbname] || opts[:db]
  socket   = opts[:socket] || opts[:sock]

  # Correct the data types before passing these values down to the C level
  user = user.to_s unless user.nil?
  pass = pass.to_s unless pass.nil?
  host = host.to_s unless host.nil?
  port = port.to_i unless port.nil?
  database = database.to_s unless database.nil?
  socket = socket.to_s unless socket.nil?

  connect user, pass, host, port, database, socket, flags
end

Instance Attribute Details

#query_optionsObject (readonly)

Returns the value of attribute query_options.



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# File 'lib/mysql2/client.rb', line 3

def query_options
  @query_options
end

#read_timeoutObject (readonly)

Returns the value of attribute read_timeout.



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# File 'lib/mysql2/client.rb', line 3

def read_timeout
  @read_timeout
end

Class Method Details

.default_query_optionsObject



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# File 'lib/mysql2/client.rb', line 5

def self.default_query_options
  @default_query_options ||= {
    :as => :hash,                   # the type of object you want each row back as; also supports :array (an array of values)
    :async => false,                # don't wait for a result after sending the query, you'll have to monitor the socket yourself then eventually call Mysql2::Client#async_result
    :cast_booleans => false,        # cast tinyint(1) fields as true/false in ruby
    :symbolize_keys => false,       # return field names as symbols instead of strings
    :database_timezone => :local,   # timezone Mysql2 will assume datetime objects are stored in
    :application_timezone => nil,   # timezone Mysql2 will convert to before handing the object back to the caller
    :cache_rows => true,            # tells Mysql2 to use its internal row cache for results
    :connect_flags => REMEMBER_OPTIONS | LONG_PASSWORD | LONG_FLAG | TRANSACTIONS | PROTOCOL_41 | SECURE_CONNECTION,
    :cast => true,
    :default_file => nil,
    :default_group => nil,
  }
end

.Mysql2::Client.escape(string) ⇒ Object

Escape string so that it may be used in a SQL statement. Note that this escape method is not connection encoding aware. If you need encoding support use Mysql2::Client#escape instead.



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# File 'ext/mysql2/client.c', line 341

static VALUE rb_mysql_client_escape(RB_MYSQL_UNUSED VALUE klass, VALUE str) {
  unsigned char *newStr;
  VALUE rb_str;
  unsigned long newLen, oldLen;

  Check_Type(str, T_STRING);

  oldLen = RSTRING_LEN(str);
  newStr = xmalloc(oldLen*2+1);

  newLen = mysql_escape_string((char *)newStr, RSTRING_PTR(str), oldLen);
  if (newLen == oldLen) {
    /* no need to return a new ruby string if nothing changed */
    xfree(newStr);
    return str;
  } else {
    rb_str = rb_str_new((const char*)newStr, newLen);
#ifdef HAVE_RUBY_ENCODING_H
    rb_enc_copy(rb_str, str);
#endif
    xfree(newStr);
    return rb_str;
  }
}

.infoObject

Returns a string that represents the client library version.



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# File 'ext/mysql2/client.c', line 942

static VALUE rb_mysql_client_info(RB_MYSQL_UNUSED VALUE klass) {
  VALUE version_info, version, header_version;
  version_info = rb_hash_new();

  version = rb_str_new2(mysql_get_client_info());
  header_version = rb_str_new2(MYSQL_LINK_VERSION);

#ifdef HAVE_RUBY_ENCODING_H
  rb_enc_associate(version, rb_usascii_encoding());
  rb_enc_associate(header_version, rb_usascii_encoding());
#endif

  rb_hash_aset(version_info, sym_id, LONG2NUM(mysql_get_client_version()));
  rb_hash_aset(version_info, sym_version, version);
  rb_hash_aset(version_info, sym_header_version, header_version);

  return version_info;
}

Instance Method Details

#abandon_results!Object

When using MULTI_STATEMENTS support, calling this will throw away any unprocessed results as fast as it can in order to put the connection back into a state where queries can be issued again.



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# File 'ext/mysql2/client.c', line 720

static VALUE rb_mysql_client_abandon_results(VALUE self) {
  MYSQL_RES *result;
  int ret;

  GET_CLIENT(self);

  while (mysql_more_results(wrapper->client) == 1) {
    ret = mysql_next_result(wrapper->client);
    if (ret > 0) {
      rb_raise_mysql2_error(wrapper);
    }

    result = (MYSQL_RES *)rb_thread_call_without_gvl(nogvl_store_result, wrapper, RUBY_UBF_IO, 0);

    if (result != NULL) {
      mysql_free_result(result);
    }
  }

  return Qnil;
}

#affected_rowsObject

returns the number of rows changed, deleted, or inserted by the last statement if it was an UPDATE, DELETE, or INSERT.



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# File 'ext/mysql2/client.c', line 1028

static VALUE rb_mysql_client_affected_rows(VALUE self) {
  my_ulonglong retVal;
  GET_CLIENT(self);

  REQUIRE_CONNECTED(wrapper);
  retVal = mysql_affected_rows(wrapper->client);
  if (retVal == (my_ulonglong)-1) {
    rb_raise_mysql2_error(wrapper);
  }
  return ULL2NUM(retVal);
}

#async_resultObject

Returns the result for the last async issued query.



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# File 'ext/mysql2/client.c', line 558

static VALUE rb_mysql_client_async_result(VALUE self) {
  MYSQL_RES * result;
  VALUE resultObj;
  VALUE current, is_streaming;
  GET_CLIENT(self);

  /* if we're not waiting on a result, do nothing */
  if (NIL_P(wrapper->active_thread))
    return Qnil;

  REQUIRE_CONNECTED(wrapper);
  if ((VALUE)rb_thread_call_without_gvl(nogvl_read_query_result, wrapper->client, RUBY_UBF_IO, 0) == Qfalse) {
    /* an error occurred, mark this connection inactive */
    wrapper->active_thread = Qnil;
    rb_raise_mysql2_error(wrapper);
  }

  is_streaming = rb_hash_aref(rb_iv_get(self, "@current_query_options"), sym_stream);
  if (is_streaming == Qtrue) {
    result = (MYSQL_RES *)rb_thread_call_without_gvl(nogvl_use_result, wrapper, RUBY_UBF_IO, 0);
  } else {
    result = (MYSQL_RES *)rb_thread_call_without_gvl(nogvl_store_result, wrapper, RUBY_UBF_IO, 0);
  }

  if (result == NULL) {
    if (mysql_errno(wrapper->client) != 0) {
      wrapper->active_thread = Qnil;
      rb_raise_mysql2_error(wrapper);
    }
    /* no data and no error, so query was not a SELECT */
    return Qnil;
  }

  current = rb_hash_dup(rb_iv_get(self, "@current_query_options"));
  (void)RB_GC_GUARD(current);
  Check_Type(current, T_HASH);
  resultObj = rb_mysql_result_to_obj(self, wrapper->encoding, current, result, Qnil);

  return resultObj;
}

#automatic_close=(false) ⇒ Object

Set this to false to leave the connection open after it is garbage collected. To avoid “Aborted connection” errors on the server, explicitly call close when the connection is no longer needed.



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# File 'ext/mysql2/client.c', line 1206

static VALUE set_automatic_close(VALUE self, VALUE value) {
  GET_CLIENT(self);
  if (RTEST(value)) {
    wrapper->automatic_close = 1;
  } else {
#ifndef _WIN32
    wrapper->automatic_close = 0;
#else
    rb_warn("Connections are always closed by garbage collector on Windows");
#endif
  }
  return value;
}

#automatic_close?Boolean

Returns:

  • (Boolean)


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# File 'ext/mysql2/client.c', line 1192

static VALUE get_automatic_close(VALUE self) {
  GET_CLIENT(self);
  return wrapper->automatic_close ? Qtrue : Qfalse;
}

#closenil

Immediately disconnect from the server; normally the garbage collector will disconnect automatically when a connection is no longer needed. Explicitly closing this will free up server resources sooner than waiting for the garbage collector.

Returns:

  • (nil)


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# File 'ext/mysql2/client.c', line 470

static VALUE rb_mysql_client_close(VALUE self) {
  GET_CLIENT(self);

  if (wrapper->client) {
    rb_thread_call_without_gvl(nogvl_close, wrapper, RUBY_UBF_IO, 0);
  }

  return Qnil;
}

#closed?Boolean

Returns:

  • (Boolean)


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# File 'ext/mysql2/client.c', line 485

static VALUE rb_mysql_client_closed(VALUE self) {
  GET_CLIENT(self);
  return CONNECTED(wrapper) ? Qfalse : Qtrue;
}

#encodingObject

Returns the encoding set on the client.



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# File 'ext/mysql2/client.c', line 1181

static VALUE rb_mysql_client_encoding(VALUE self) {
  GET_CLIENT(self);
  return wrapper->encoding;
}

#escape(string) ⇒ Object

Escape string so that it may be used in a SQL statement.



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# File 'ext/mysql2/client.c', line 801

static VALUE rb_mysql_client_real_escape(VALUE self, VALUE str) {
  unsigned char *newStr;
  VALUE rb_str;
  unsigned long newLen, oldLen;
#ifdef HAVE_RUBY_ENCODING_H
  rb_encoding *default_internal_enc;
  rb_encoding *conn_enc;
#endif
  GET_CLIENT(self);

  REQUIRE_CONNECTED(wrapper);
  Check_Type(str, T_STRING);
#ifdef HAVE_RUBY_ENCODING_H
  default_internal_enc = rb_default_internal_encoding();
  conn_enc = rb_to_encoding(wrapper->encoding);
  /* ensure the string is in the encoding the connection is expecting */
  str = rb_str_export_to_enc(str, conn_enc);
#endif

  oldLen = RSTRING_LEN(str);
  newStr = xmalloc(oldLen*2+1);

  newLen = mysql_real_escape_string(wrapper->client, (char *)newStr, RSTRING_PTR(str), oldLen);
  if (newLen == oldLen) {
    /* no need to return a new ruby string if nothing changed */
#ifdef HAVE_RUBY_ENCODING_H
    if (default_internal_enc) {
      str = rb_str_export_to_enc(str, default_internal_enc);
    }
#endif
    xfree(newStr);
    return str;
  } else {
    rb_str = rb_str_new((const char*)newStr, newLen);
#ifdef HAVE_RUBY_ENCODING_H
    rb_enc_associate(rb_str, conn_enc);
    if (default_internal_enc) {
      rb_str = rb_str_export_to_enc(rb_str, default_internal_enc);
    }
#endif
    xfree(newStr);
    return rb_str;
  }
}

#infoObject



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# File 'lib/mysql2/client.rb', line 137

def info
  self.class.info
end

#last_idObject

Returns the value generated for an AUTO_INCREMENT column by the previous INSERT or UPDATE statement.



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# File 'ext/mysql2/client.c', line 1016

static VALUE rb_mysql_client_last_id(VALUE self) {
  GET_CLIENT(self);
  REQUIRE_CONNECTED(wrapper);
  return ULL2NUM(mysql_insert_id(wrapper->client));
}

#more_results?Boolean

Returns true or false if there are more results to process.

Returns:

  • (Boolean)


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# File 'ext/mysql2/client.c', line 1114

static VALUE rb_mysql_client_more_results(VALUE self)
{
  GET_CLIENT(self);
  if (mysql_more_results(wrapper->client) == 0)
    return Qfalse;
  else
    return Qtrue;
}

#next_resultObject

Fetch the next result set from the server. Returns nothing.



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# File 'ext/mysql2/client.c', line 1129

static VALUE rb_mysql_client_next_result(VALUE self)
{
    int ret;
    GET_CLIENT(self);
    ret = mysql_next_result(wrapper->client);
    if (ret > 0) {
      rb_raise_mysql2_error(wrapper);
      return Qfalse;
    } else if (ret == 0) {
      return Qtrue;
    } else {
      return Qfalse;
    }
}

#parse_flags_array(flags, initial = 0) ⇒ Object



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# File 'lib/mysql2/client.rb', line 103

def parse_flags_array(flags, initial = 0)
  flags.reduce(initial) do |memo, f|
    fneg = f.start_with?('-') ? f[1..-1] : nil
    if fneg && fneg =~ /^\w+$/ && Mysql2::Client.const_defined?(fneg)
      memo & ~ Mysql2::Client.const_get(fneg)
    elsif f && f =~ /^\w+$/ && Mysql2::Client.const_defined?(f)
      memo | Mysql2::Client.const_get(f)
    else
      warn "Unknown MySQL connection flag: '#{f}'"
      memo
    end
  end
end

#parse_ssl_mode(mode) ⇒ Object



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# File 'lib/mysql2/client.rb', line 92

def parse_ssl_mode(mode)
  m = mode.to_s.upcase
  if m.start_with?('SSL_MODE_')
    return Mysql2::Client.const_get(m) if Mysql2::Client.const_defined?(m)
  else
    x = 'SSL_MODE_' + m
    return Mysql2::Client.const_get(x) if Mysql2::Client.const_defined?(x)
  end
  warn "Unknown MySQL ssl_mode flag: #{mode}"
end

#pingObject

Checks whether the connection to the server is working. If the connection has gone down and auto-reconnect is enabled an attempt to reconnect is made. If the connection is down and auto-reconnect is disabled, ping returns an error.



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# File 'ext/mysql2/client.c', line 1099

static VALUE rb_mysql_client_ping(VALUE self) {
  GET_CLIENT(self);

  if (!CONNECTED(wrapper)) {
    return Qfalse;
  } else {
    return (VALUE)rb_thread_call_without_gvl(nogvl_ping, wrapper->client, RUBY_UBF_IO, 0);
  }
}

#prepare(sql) ⇒ Object

Create a new prepared statement.



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# File 'ext/mysql2/client.c', line 1354

static VALUE rb_mysql_client_prepare_statement(VALUE self, VALUE sql) {
  GET_CLIENT(self);
  REQUIRE_CONNECTED(wrapper);

  return rb_mysql_stmt_new(self, sql);
}

#query(sql, options = {}) ⇒ Object



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# File 'lib/mysql2/client.rb', line 118

def query(sql, options = {})
  Thread.handle_interrupt(::Mysql2::Util::TimeoutError => :never) do
    _query(sql, @query_options.merge(options))
  end
end

#query_infoObject



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# File 'lib/mysql2/client.rb', line 129

def query_info
  info = query_info_string
  return {} unless info
  info_hash = {}
  info.split.each_slice(2) { |s| info_hash[s[0].downcase.delete(':').to_sym] = s[1].to_i }
  info_hash
end

#query_info_stringObject



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# File 'ext/mysql2/client.c', line 375

static VALUE rb_mysql_info(VALUE self) {
  const char *info;
  VALUE rb_str;
  GET_CLIENT(self);

  info = mysql_info(wrapper->client);

  if (info == NULL) {
    return Qnil;
  }

  rb_str = rb_str_new2(info);
#ifdef HAVE_RUBY_ENCODING_H
  rb_enc_associate(rb_str, rb_utf8_encoding());
#endif

  return rb_str;
}

#reconnect=(true) ⇒ Object

Enable or disable the automatic reconnect behavior of libmysql. Read dev.mysql.com/doc/refman/5.5/en/auto-reconnect.html for more information.



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# File 'ext/mysql2/client.c', line 1227

static VALUE set_reconnect(VALUE self, VALUE value) {
  return _mysql_client_options(self, MYSQL_OPT_RECONNECT, value);
}

#select_db(name) ⇒ Object

Causes the database specified by name to become the default (current) database on the connection specified by mysql.



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# File 'ext/mysql2/client.c', line 1069

static VALUE rb_mysql_client_select_db(VALUE self, VALUE db)
{
  struct nogvl_select_db_args args;

  GET_CLIENT(self);
  REQUIRE_CONNECTED(wrapper);

  args.mysql = wrapper->client;
  args.db = StringValueCStr(db);

  if (rb_thread_call_without_gvl(nogvl_select_db, &args, RUBY_UBF_IO, 0) == Qfalse)
    rb_raise_mysql2_error(wrapper);

  return db;
}

#server_infoObject

Returns a string that represents the server version number



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# File 'ext/mysql2/client.c', line 966

static VALUE rb_mysql_client_server_info(VALUE self) {
  VALUE version, server_info;
#ifdef HAVE_RUBY_ENCODING_H
  rb_encoding *default_internal_enc;
  rb_encoding *conn_enc;
#endif
  GET_CLIENT(self);

  REQUIRE_CONNECTED(wrapper);
#ifdef HAVE_RUBY_ENCODING_H
  default_internal_enc = rb_default_internal_encoding();
  conn_enc = rb_to_encoding(wrapper->encoding);
#endif

  version = rb_hash_new();
  rb_hash_aset(version, sym_id, LONG2FIX(mysql_get_server_version(wrapper->client)));
  server_info = rb_str_new2(mysql_get_server_info(wrapper->client));
#ifdef HAVE_RUBY_ENCODING_H
  rb_enc_associate(server_info, conn_enc);
  if (default_internal_enc) {
    server_info = rb_str_export_to_enc(server_info, default_internal_enc);
  }
#endif
  rb_hash_aset(version, sym_version, server_info);
  return version;
}

#socketObject



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# File 'ext/mysql2/client.c', line 1005

static VALUE rb_mysql_client_socket(RB_MYSQL_UNUSED VALUE self) {
  rb_raise(cMysql2Error, "Raw access to the mysql file descriptor isn't supported on Windows");
}

#ssl_cipherObject



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# File 'ext/mysql2/client.c', line 394

static VALUE rb_mysql_get_ssl_cipher(VALUE self)
{
  const char *cipher;
  VALUE rb_str;
  GET_CLIENT(self);

  cipher = mysql_get_ssl_cipher(wrapper->client);

  if (cipher == NULL) {
    return Qnil;
  }

  rb_str = rb_str_new2(cipher);
#ifdef HAVE_RUBY_ENCODING_H
  rb_enc_associate(rb_str, rb_utf8_encoding());
#endif

  return rb_str;
}

#store_resultObject

Return the next result object from a query which yielded multiple result sets.



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# File 'ext/mysql2/client.c', line 1150

static VALUE rb_mysql_client_store_result(VALUE self)
{
  MYSQL_RES * result;
  VALUE resultObj;
  VALUE current;
  GET_CLIENT(self);

  result = (MYSQL_RES *)rb_thread_call_without_gvl(nogvl_store_result, wrapper, RUBY_UBF_IO, 0);

  if (result == NULL) {
    if (mysql_errno(wrapper->client) != 0) {
      rb_raise_mysql2_error(wrapper);
    }
    /* no data and no error, so query was not a SELECT */
    return Qnil;
  }

  current = rb_hash_dup(rb_iv_get(self, "@current_query_options"));
  (void)RB_GC_GUARD(current);
  Check_Type(current, T_HASH);
  resultObj = rb_mysql_result_to_obj(self, wrapper->encoding, current, result, Qnil);

  return resultObj;
}

#thread_idObject

Returns the thread ID of the current connection.



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# File 'ext/mysql2/client.c', line 1045

static VALUE rb_mysql_client_thread_id(VALUE self) {
  unsigned long retVal;
  GET_CLIENT(self);

  REQUIRE_CONNECTED(wrapper);
  retVal = mysql_thread_id(wrapper->client);
  return ULL2NUM(retVal);
}

#warning_countObject



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# File 'ext/mysql2/client.c', line 366

static VALUE rb_mysql_client_warning_count(VALUE self) {
  unsigned int warning_count;
  GET_CLIENT(self);

  warning_count = mysql_warning_count(wrapper->client);

  return UINT2NUM(warning_count);
}