class Sequel::SQLite::Database
Attributes
The conversion procs to use for this database
Public Class Methods
Sequel::Database::new
# File lib/sequel/adapters/sqlite.rb 101 def initialize(opts = OPTS) 102 super 103 @allow_regexp = typecast_value_boolean(opts[:setup_regexp_function]) 104 end
Public Instance Methods
Connect to the database. Since SQLite
is a file based database, available options are limited:
- :database
-
database name (filename or ‘:memory:’ or file: URI)
- :readonly
-
open database in read-only mode; useful for reading static data that you do not want to modify
- :timeout
-
how long to wait for the database to be available if it is locked, given in milliseconds (default is 5000)
- :setup_regexp_function
-
enable use of Regexp objects with
SQL
'REGEXP' operator. If the value is :cached or "cached", caches the generated regexps, which can result in a memory leak if dynamic regexps are used. If the value is a Proc, it will be called with a string for the regexp and a string for the value to compare, and should return whether the regexp matches.
# File lib/sequel/adapters/sqlite.rb 121 def connect(server) 122 opts = server_opts(server) 123 opts[:database] = ':memory:' if blank_object?(opts[:database]) 124 sqlite3_opts = {} 125 sqlite3_opts[:readonly] = typecast_value_boolean(opts[:readonly]) if opts.has_key?(:readonly) 126 db = ::SQLite3::Database.new(opts[:database].to_s, sqlite3_opts) 127 db.busy_timeout(typecast_value_integer(opts.fetch(:timeout, 5000))) 128 129 if USE_EXTENDED_RESULT_CODES 130 db.extended_result_codes = true 131 end 132 133 connection_pragmas.each{|s| log_connection_yield(s, db){db.execute_batch(s)}} 134 135 if typecast_value_boolean(opts[:setup_regexp_function]) 136 setup_regexp_function(db, opts[:setup_regexp_function]) 137 end 138 139 class << db 140 attr_reader :prepared_statements 141 end 142 db.instance_variable_set(:@prepared_statements, {}) 143 144 db 145 end
Disconnect given connections from the database.
# File lib/sequel/adapters/sqlite.rb 154 def disconnect_connection(c) 155 c.prepared_statements.each_value{|v| v.first.close} 156 c.close 157 end
Run the given SQL
with the given arguments and yield each row.
# File lib/sequel/adapters/sqlite.rb 160 def execute(sql, opts=OPTS, &block) 161 _execute(:select, sql, opts, &block) 162 end
Drop any prepared statements on the connection when executing DDL. This is because prepared statements lock the table in such a way that you can’t drop or alter the table while a prepared statement that references it still exists.
Sequel::Database#execute_ddl
# File lib/sequel/adapters/sqlite.rb 172 def execute_ddl(sql, opts=OPTS) 173 synchronize(opts[:server]) do |conn| 174 conn.prepared_statements.values.each{|cps, s| cps.close} 175 conn.prepared_statements.clear 176 super 177 end 178 end
Run the given SQL
with the given arguments and return the number of changed rows.
# File lib/sequel/adapters/sqlite.rb 165 def execute_dui(sql, opts=OPTS) 166 _execute(:update, sql, opts) 167 end
# File lib/sequel/adapters/sqlite.rb 180 def execute_insert(sql, opts=OPTS) 181 _execute(:insert, sql, opts) 182 end
Sequel::SQLite::DatabaseMethods#freeze
# File lib/sequel/adapters/sqlite.rb 184 def freeze 185 @conversion_procs.freeze 186 super 187 end
Handle Integer and Float arguments, since SQLite
can store timestamps as integers and floats.
Sequel::Database#to_application_timestamp
# File lib/sequel/adapters/sqlite.rb 190 def to_application_timestamp(s) 191 case s 192 when String 193 super 194 when Integer 195 super(Time.at(s).to_s) 196 when Float 197 super(DateTime.jd(s).to_s) 198 else 199 raise Sequel::Error, "unhandled type when converting to : #{s.inspect} (#{s.class.inspect})" 200 end 201 end
Private Instance Methods
Yield an available connection. Rescue any SQLite3::Exceptions and turn them into DatabaseErrors.
# File lib/sequel/adapters/sqlite.rb 229 def _execute(type, sql, opts, &block) 230 synchronize(opts[:server]) do |conn| 231 return execute_prepared_statement(conn, type, sql, opts, &block) if sql.is_a?(Symbol) 232 log_args = opts[:arguments] 233 args = {} 234 opts.fetch(:arguments, OPTS).each{|k, v| args[k] = prepared_statement_argument(v)} 235 case type 236 when :select 237 log_connection_yield(sql, conn, log_args){conn.query(sql, args, &block)} 238 when :insert 239 log_connection_yield(sql, conn, log_args){conn.execute(sql, args)} 240 conn.last_insert_row_id 241 when :update 242 log_connection_yield(sql, conn, log_args){conn.execute_batch(sql, args)} 243 conn.changes 244 end 245 end 246 rescue SQLite3::Exception => e 247 raise_error(e) 248 end
# File lib/sequel/adapters/sqlite.rb 205 def adapter_initialize 206 @conversion_procs = SQLITE_TYPES.dup 207 @conversion_procs['datetime'] = @conversion_procs['timestamp'] = method(:to_application_timestamp) 208 set_integer_booleans 209 end
The SQLite
adapter does not need the pool to convert exceptions. Also, force the max connections to 1 if a memory database is being used, as otherwise each connection gets a separate database.
Sequel::Database#connection_pool_default_options
# File lib/sequel/adapters/sqlite.rb 253 def connection_pool_default_options 254 o = super.dup 255 # Default to only a single connection if a memory database is used, 256 # because otherwise each connection will get a separate database 257 o[:max_connections] = 1 if @opts[:database] == ':memory:' || blank_object?(@opts[:database]) 258 o 259 end
SQLite3 raises ArgumentError in addition to SQLite3::Exception in some cases, such as operations on a closed database.
# File lib/sequel/adapters/sqlite.rb 318 def database_error_classes 319 [SQLite3::Exception, ArgumentError] 320 end
# File lib/sequel/adapters/sqlite.rb 322 def dataset_class_default 323 Dataset 324 end
Execute a prepared statement on the database using the given name.
# File lib/sequel/adapters/sqlite.rb 279 def execute_prepared_statement(conn, type, name, opts, &block) 280 ps = prepared_statement(name) 281 sql = ps.prepared_sql 282 args = opts[:arguments] 283 ps_args = {} 284 args.each{|k, v| ps_args[k] = prepared_statement_argument(v)} 285 if cpsa = conn.prepared_statements[name] 286 cps, cps_sql = cpsa 287 if cps_sql != sql 288 cps.close 289 cps = nil 290 end 291 end 292 unless cps 293 cps = log_connection_yield("PREPARE #{name}: #{sql}", conn){conn.prepare(sql)} 294 conn.prepared_statements[name] = [cps, sql] 295 end 296 log_sql = String.new 297 log_sql << "EXECUTE #{name}" 298 if ps.log_sql 299 log_sql << " (" 300 log_sql << sql 301 log_sql << ")" 302 end 303 if block 304 log_connection_yield(log_sql, conn, args){cps.execute(ps_args, &block)} 305 else 306 log_connection_yield(log_sql, conn, args){cps.execute!(ps_args){|r|}} 307 case type 308 when :insert 309 conn.last_insert_row_id 310 when :update 311 conn.changes 312 end 313 end 314 end
# File lib/sequel/adapters/sqlite.rb 261 def prepared_statement_argument(arg) 262 case arg 263 when Date, DateTime, Time 264 literal(arg)[1...-1] 265 when SQL::Blob 266 arg.to_blob 267 when true, false 268 if integer_booleans 269 arg ? 1 : 0 270 else 271 literal(arg)[1...-1] 272 end 273 else 274 arg 275 end 276 end
# File lib/sequel/adapters/sqlite.rb 211 def setup_regexp_function(db, how) 212 case how 213 when Proc 214 # nothing 215 when :cached, "cached" 216 cache = Hash.new{|h,k| h[k] = Regexp.new(k)} 217 how = lambda{|regexp_str, str| cache[regexp_str].match(str)} 218 else 219 how = lambda{|regexp_str, str| Regexp.new(regexp_str).match(str)} 220 end 221 222 db.create_function("regexp", 2) do |func, regexp_str, str| 223 func.result = how.call(regexp_str, str) ? 1 : 0 224 end 225 end
Support SQLite
exception codes if ruby-sqlite3 supports them.
# File lib/sequel/adapters/sqlite.rb 328 def sqlite_error_code(exception) 329 exception.code if exception.respond_to?(:code) 330 end