Module: ActiveRecord::ConnectionAdapters::SQLite3::SchemaStatements

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 56

def add_foreign_key(from_table, to_table, **options)
  assert_valid_deferrable(options[:deferrable])

  alter_table(from_table) do |definition|
    to_table = strip_table_name_prefix_and_suffix(to_table)
    definition.foreign_key(to_table, **options)
  end
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 207

def assert_valid_deferrable(deferrable)
  return if !deferrable || %i(immediate deferred).include?(deferrable)

  raise ArgumentError, "deferrable must be `:immediate` or `:deferred`, got: `#{deferrable.inspect}`"
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 90

def check_constraints(table_name)
  table_sql = query_value(<<-SQL, "SCHEMA")
    SELECT sql
    FROM sqlite_master
    WHERE name = #{quote(table_name)} AND type = 'table'
    UNION ALL
    SELECT sql
    FROM sqlite_temp_master
    WHERE name = #{quote(table_name)} AND type = 'table'
  SQL

  table_sql.to_s.scan(/CONSTRAINT\s(?<name>\w)\sCHECK\s\((?<expression>(:?[^()]|\(\g<expression>\))+)\)/i).map do |name, expression|
    CheckConstraintDefinition.new(table_name, expression, name: name)
  end
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 121

def create_schema_dumper(options)
  SQLite3::SchemaDumper.create(self, options)
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 134

def create_table_definition(name, **options)
  SQLite3::TableDefinition.new(self, name, **options)
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 180

def data_source_sql(name = nil, type: nil)
  scope = quoted_scope(name, type: type)
  scope[:type] ||= "'table','view'"

  sql = +"SELECT name FROM pragma_table_list WHERE schema <> 'temp'"
  sql << " AND name NOT IN ('sqlite_sequence', 'sqlite_schema')"
  sql << " AND name = #{scope[:name]}" if scope[:name]
  sql << " AND type IN (#{scope[:type]})"
  sql
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 213

def extract_generated_type(field)
  case field["hidden"]
  when 2 then :virtual
  when 3 then :stored
  end
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 8

def indexes(table_name)
  internal_exec_query("PRAGMA index_list(#{quote_table_name(table_name)})", "SCHEMA").filter_map do |row|
    # Indexes SQLite creates implicitly for internal use start with "sqlite_".
    # See https://www.sqlite.org/fileformat2.html#intschema
    next if row["name"].start_with?("sqlite_")

    index_sql = query_value(<<~SQL, "SCHEMA")
      SELECT sql
      FROM sqlite_master
      WHERE name = #{quote(row['name'])} AND type = 'index'
      UNION ALL
      SELECT sql
      FROM sqlite_temp_master
      WHERE name = #{quote(row['name'])} AND type = 'index'
    SQL

    /\bON\b\s*"?(\w?)"?\s*\((?<expressions>.?)\)(?:\s*WHERE\b\s*(?<where>.+))?(?:\s*\/\*.*\*\/)?\z/i =~ index_sql

    columns = internal_exec_query("PRAGMA index_info(#{quote(row['name'])})", "SCHEMA").map do |col|
      col["name"]
    end

    where = where.sub(/\s*\/\*.*\*\/\z/, "") if where
    orders = {}

    if columns.any?(&:nil?) # index created with an expression
      columns = expressions
    else
      # Add info on sort order for columns (only desc order is explicitly specified,
      # asc is the default)
      if index_sql # index_sql can be null in case of primary key indexes
        index_sql.scan(/"(\w+)" DESC/).flatten.each { |order_column|
          orders[order_column] = :desc
        }
      end
    end

    IndexDefinition.new(
      table_name,
      row["name"],
      row["unique"] != 0,
      columns,
      where: where,
      orders: orders
    )
  end
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 174

def is_column_the_rowid?(field, column_definitions)
  return false unless INTEGER_REGEX.match?(field["type"]) && field["pk"] == 1
  # is the primary key a single column?
  column_definitions.one? { |c| c["pk"] > 0 }
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 142

def new_column_from_field(table_name, field, definitions)
  default = field["dflt_value"]

  type_metadata = fetch_type_metadata(field["type"])
  default_value = extract_value_from_default(default)
  generated_type = extract_generated_type(field)

  if generated_type.present?
    default_function = default
  else
    default_function = extract_default_function(default_value, default)
  end

  rowid = is_column_the_rowid?(field, definitions)

  Column.new(
    field["name"],
    default_value,
    type_metadata,
    field["notnull"].to_i == 0,
    default_function,
    collation: field["collation"],
    auto_increment: field["auto_increment"],
    rowid: rowid,
    generated_type: generated_type
  )
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 191

def quoted_scope(name = nil, type: nil)
  type = \
    case type
    when "BASE TABLE"
      "'table'"
    when "VIEW"
      "'view'"
    when "VIRTUAL TABLE"
      "'virtual'"
    end
  scope = {}
  scope[:name] = quote(name) if name
  scope[:type] = type if type
  scope
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 112

def remove_check_constraint(table_name, expression = nil, if_exists: false, **options)
  return if if_exists && !check_constraint_exists?(table_name, **options)

  check_constraints = check_constraints(table_name)
  chk_name_to_delete = check_constraint_for!(table_name, expression: expression, **options).name
  check_constraints.delete_if { |chk| chk.name == chk_name_to_delete }
  alter_table(table_name, foreign_keys(table_name), check_constraints)
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 65

def remove_foreign_key(from_table, to_table = nil, **options)
  return if options.delete(:if_exists) == true && !foreign_key_exists?(from_table, to_table)

  to_table ||= options[:to_table]
  options = options.except(:name, :to_table, :validate)
  foreign_keys = foreign_keys(from_table)

  fkey = foreign_keys.detect do |fk|
    table = to_table || begin
      table = options[:column].to_s.delete_suffix("_id")
      Base.pluralize_table_names ? table.pluralize : table
    end
    table = strip_table_name_prefix_and_suffix(table)
    fk_to_table = strip_table_name_prefix_and_suffix(fk.to_table)
    fk_to_table == table && options.all? { |k, v| fk.options[k].to_s == v.to_s }
  end || raise(ArgumentError, "Table '#{from_table}' has no foreign key for #{to_table || options}")

  foreign_keys.delete(fkey)
  alter_table(from_table, foreign_keys)
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 125

def schema_creation # :nodoc
  SQLite3::SchemaCreation.new(self)
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 130

def valid_table_definition_options
  super + [:rename]
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 138

def validate_index_length!(table_name, new_name, internal = false)
  super unless internal
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 86

def virtual_table_exists?(table_name)
  query_values(data_source_sql(table_name, type: "VIRTUAL TABLE"), "SCHEMA").any?
end