Module Sequel::MySQL::DatabaseMethods
In: lib/sequel/adapters/shared/mysql.rb

Methods shared by Database instances that connect to MySQL, currently supported by the native and JDBC adapters.

Methods

Included Modules

Sequel::Database::SplitAlterTable

Constants

AUTO_INCREMENT = 'AUTO_INCREMENT'.freeze
CAST_TYPES = {String=>:CHAR, Integer=>:SIGNED, Time=>:DATETIME, DateTime=>:DATETIME, Numeric=>:DECIMAL, BigDecimal=>:DECIMAL, File=>:BINARY}
COLUMN_DEFINITION_ORDER = [:collate, :null, :default, :unique, :primary_key, :auto_increment, :references]
PRIMARY = 'PRIMARY'.freeze
MYSQL_TIMESTAMP_RE = /\ACURRENT_(?:DATE|TIMESTAMP)?\z/
DATABASE_ERROR_REGEXPS = { /Duplicate entry .+ for key/ => UniqueConstraintViolation, /foreign key constraint fails/ => ForeignKeyConstraintViolation, /cannot be null/ => NotNullConstraintViolation, /Deadlock found when trying to get lock; try restarting transaction/ => SerializationFailure, }.freeze

Public Instance methods

MySQL‘s cast rules are restrictive in that you can‘t just cast to any possible database type.

[Source]

    # File lib/sequel/adapters/shared/mysql.rb, line 57
57:       def cast_type_literal(type)
58:         CAST_TYPES[type] || super
59:       end

Commit an existing prepared transaction with the given transaction identifier string.

[Source]

    # File lib/sequel/adapters/shared/mysql.rb, line 63
63:       def commit_prepared_transaction(transaction_id, opts=OPTS)
64:         run("XA COMMIT #{literal(transaction_id)}", opts)
65:       end

MySQL uses the :mysql database type

[Source]

    # File lib/sequel/adapters/shared/mysql.rb, line 68
68:       def database_type
69:         :mysql
70:       end

Use the Information Schema‘s KEY_COLUMN_USAGE table to get basic information on foreign key columns, but include the constraint name.

[Source]

    # File lib/sequel/adapters/shared/mysql.rb, line 75
75:       def foreign_key_list(table, opts=OPTS)
76:         m = output_identifier_meth
77:         im = input_identifier_meth
78:         ds = metadata_dataset.
79:           from(:INFORMATION_SCHEMA__KEY_COLUMN_USAGE).
80:           where(:TABLE_NAME=>im.call(table), :TABLE_SCHEMA=>Sequel.function(:DATABASE)).
81:           exclude(:CONSTRAINT_NAME=>'PRIMARY').
82:           exclude(:REFERENCED_TABLE_NAME=>nil).
83:           select(:CONSTRAINT_NAME___name, :COLUMN_NAME___column, :REFERENCED_TABLE_NAME___table, :REFERENCED_COLUMN_NAME___key)
84:         
85:         h = {}
86:         ds.each do |row|
87:           if r = h[row[:name]]
88:             r[:columns] << m.call(row[:column])
89:             r[:key] << m.call(row[:key])
90:           else
91:             h[row[:name]] = {:name=>m.call(row[:name]), :columns=>[m.call(row[:column])], :table=>m.call(row[:table]), :key=>[m.call(row[:key])]}
92:           end
93:         end
94:         h.values
95:       end

MySQL namespaces indexes per table.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 98
 98:       def global_index_namespace?
 99:         false
100:       end

Use SHOW INDEX FROM to get the index information for the table.

By default partial indexes are not included, you can use the option :partial to override this.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 107
107:       def indexes(table, opts=OPTS)
108:         indexes = {}
109:         remove_indexes = []
110:         m = output_identifier_meth
111:         im = input_identifier_meth
112:         metadata_dataset.with_sql("SHOW INDEX FROM ?", SQL::Identifier.new(im.call(table))).each do |r|
113:           name = r[:Key_name]
114:           next if name == PRIMARY
115:           name = m.call(name)
116:           remove_indexes << name if r[:Sub_part] && ! opts[:partial]
117:           i = indexes[name] ||= {:columns=>[], :unique=>r[:Non_unique] != 1}
118:           i[:columns] << m.call(r[:Column_name])
119:         end
120:         indexes.reject{|k,v| remove_indexes.include?(k)}
121:       end

Rollback an existing prepared transaction with the given transaction identifier string.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 125
125:       def rollback_prepared_transaction(transaction_id, opts=OPTS)
126:         run("XA ROLLBACK #{literal(transaction_id)}", opts)
127:       end

Get version of MySQL server, used for determined capabilities.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 130
130:       def server_version
131:         @server_version ||= begin
132:           m = /(\d+)\.(\d+)\.(\d+)/.match(get(SQL::Function.new(:version)))
133:           (m[1].to_i * 10000) + (m[2].to_i * 100) + m[3].to_i
134:         end
135:       end

MySQL supports CREATE TABLE IF NOT EXISTS syntax.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 138
138:       def supports_create_table_if_not_exists?
139:         true
140:       end

MySQL 5+ supports prepared transactions (two-phase commit) using XA

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 143
143:       def supports_prepared_transactions?
144:         server_version >= 50000
145:       end

MySQL 5+ supports savepoints

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 148
148:       def supports_savepoints?
149:         server_version >= 50000
150:       end

MySQL doesn‘t support savepoints inside prepared transactions in from 5.5.12 to 5.5.23, see bugs.mysql.com/bug.php?id=64374

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 154
154:       def supports_savepoints_in_prepared_transactions?
155:         super && (server_version <= 50512 || server_version >= 50523)
156:       end

Support fractional timestamps on MySQL 5.6.5+ if the :fractional_seconds Database option is used. Technically, MySQL 5.6.4+ supports them, but automatic initialization of datetime values wasn‘t supported to 5.6.5+, and this is related to that.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 162
162:       def supports_timestamp_usecs?
163:         @supports_timestamp_usecs ||= server_version >= 50605 && typecast_value_boolean(opts[:fractional_seconds])
164:       end

MySQL supports transaction isolation levels

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 167
167:       def supports_transaction_isolation_levels?
168:         true
169:       end

Return an array of symbols specifying table names in the current database.

Options:

:server :Set the server to use

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 175
175:       def tables(opts=OPTS)
176:         full_tables('BASE TABLE', opts)
177:       end

Changes the database in use by issuing a USE statement. I would be very careful if I used this.

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 181
181:       def use(db_name)
182:         disconnect
183:         @opts[:database] = db_name if self << "USE #{db_name}"
184:         @schemas = {}
185:         self
186:       end

Return an array of symbols specifying view names in the current database.

Options:

:server :Set the server to use

[Source]

     # File lib/sequel/adapters/shared/mysql.rb, line 192
192:       def views(opts=OPTS)
193:         full_tables('VIEW', opts)
194:       end

[Validate]