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

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 13

def add_foreign_key(from_table, to_table, if_not_exists: false, **options)
  options = foreign_key_options(from_table, to_table, options)
  return if if_not_exists && foreign_key_exists?(from_table, to_table, **options.slice(:column, :primary_key))

  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 241

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 123

def build_index(table_name, row, index_sql, columns)
  /\bON\b\s*"?(\w?)"?\s*\((?<expressions>.?)\)(?:\s*WHERE\b\s*(?<where>.+?))?(?:\s*\/\*.*\*\/)?\s*\z/im =~ index_sql

  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

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 41

def check_constraints(table_name)
  result = fetch_check_constraints(Array(table_name).map(&:to_s))
  table_name.is_a?(Array) ? result : result[table_name.to_s]
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 63

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

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 167

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 214

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 247

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 151

def fetch_check_constraints(tables)
  structures = table_structures(tables)

  tables.index_with do |table_name|
    create_table_sql, = structures[table_name]

    create_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
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 82

def fetch_indexes(tables)
  return {} if tables.empty?

  rows = query_all(<<~SQL).group_by { |row| row["table_name"] }
    #{MASTER_CTE}
    SELECT m.name AS table_name, i.name, i."unique"
    FROM master m
    JOIN pragma_index_list(m.name) i
    WHERE m.type = 'table'
      AND m.name IN (#{quoted_table_names(tables)})
      AND i.name NOT GLOB 'sqlite_*'
  SQL

  details = index_details(rows.each_value.flat_map { |group| group.map { |row| row["name"] } })

  tables.index_with do |table_name|
    rows.fetch(table_name, []).map do |row|
      index_sql, columns = details[row["name"]] || [nil, []]

      build_index(table_name, row, index_sql, columns)
    end
  end
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 108

def index_details(names)
  return {} if names.empty?

  query_all(<<~SQL).group_by { |row| row["index_name"] }
    #{MASTER_CTE}
    SELECT m.name AS index_name, m.sql, i.name
    FROM master m
    JOIN pragma_index_info(m.name) i
    WHERE m.type = 'index'
      AND m.name IN (#{names.map { |name| quote(name) }.join(", ")})
    ORDER BY m.name, i.seqno
  SQL
    .transform_values { |group| [group.first["sql"], group.map { |row| row["name"] }] }
end

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

def indexes(table_name)
  result = fetch_indexes(Array(table_name).map(&:to_s))
  table_name.is_a?(Array) ? result : result[table_name.to_s]
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 208

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 175

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"],
    lookup_cast_type(field["type"]),
    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 225

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 54

def remove_check_constraint(table_name, expression = nil, if_exists: false, **options)
  return if if_exists && !check_constraint_exists?(table_name, expression: expression, **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 25

def remove_foreign_key(from_table, to_table = nil, **options)
  to_table ||= options[:to_table]
  return if options.delete(:if_exists) && !foreign_key_exists?(from_table, to_table, **options.slice(:column, :name))

  options = options.except(:to_table, :validate)
  fkey = foreign_key_for!(from_table, to_table: to_table, **options)

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

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 67

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

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 163

def valid_table_definition_options
  super + [:rename]
end

# File 'activerecord/lib/active_record/connection_adapters/sqlite3/schema_statements.rb', line 171

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 37

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