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module ActiveRecord::ConnectionAdapters::DatabaseLimits
Public Instance Methods
Returns the maximum allowed length for an index name. This limit is enforced by rails and Is less than or equal to index_name_length
. The gap between index_name_length
is to allow internal rails operations to use prefixes in temporary operations.
# File activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb, line 25
def allowed_index_name_length
index_name_length
end
Returns the maximum length of a column name.
# File activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb, line 11
def column_name_length
64
end
Returns the maximum number of columns in a multicolumn index.
# File activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb, line 45
def columns_per_multicolumn_index
16
end
Returns the maximum number of columns per table.
# File activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb, line 35
def columns_per_table
1024
end
Returns the maximum number of elements in an IN (x,y,z) clause. nil means no limit.
# File activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb, line 51
def in_clause_length
nil
end
Returns the maximum length of an index name.
# File activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb, line 30
def index_name_length
64
end
Returns the maximum number of indexes per table.
# File activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb, line 40
def indexes_per_table
16
end
Returns maximum number of joins in a single query.
# File activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb, line 61
def joins_per_query
256
end
Returns the maximum length of an SQL query.
# File activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb, line 56
def sql_query_length
1048575
end
Returns the maximum length of a table alias.
# File activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb, line 6
def table_alias_length
255
end
Returns the maximum length of a table name.
# File activerecord/lib/active_record/connection_adapters/abstract/database_limits.rb, line 16
def table_name_length
64
end
© 2004–2016 David Heinemeier Hansson
Licensed under the MIT License.