Module: Sequel::Access::DatasetMethods
- Included in:
- Sequel::ADO::Access::Dataset
- Defined in:
- lib/sequel/adapters/shared/access.rb
Constant Summary collapse
- EXTRACT_MAP =
{:year=>"'yyyy'", :month=>"'m'", :day=>"'d'", :hour=>"'h'", :minute=>"'n'", :second=>"'s'"}.freeze
- OPS =
{:'%'=>' Mod '.freeze, :'||'=>' & '.freeze}.freeze
- CAST_TYPES =
{String=>:CStr, Integer=>:CLng, Date=>:CDate, Time=>:CDate, DateTime=>:CDate, Numeric=>:CDec, BigDecimal=>:CDec, File=>:CStr, Float=>:CDbl, TrueClass=>:CBool, FalseClass=>:CBool}.freeze
Instance Method Summary collapse
-
#case_expression_sql_append(sql, ce) ⇒ Object
Access doesn't support CASE, so emulate it with nested IIF function calls.
-
#cast_sql_append(sql, expr, type) ⇒ Object
Access doesn't support CAST, it uses separate functions for type conversion.
- #complex_expression_sql_append(sql, op, args) ⇒ Object
-
#constant_sql_append(sql, constant) ⇒ Object
Use Date(), Now(), and Time() for CURRENT_DATE, CURRENT_TIMESTAMP, and CURRENT_TIME.
-
#cross_join(table) ⇒ Object
Emulate cross join by using multiple tables in the FROM clause.
-
#escape_like(string) ⇒ Object
Access uses [] to escape metacharacters, instead of backslashes.
-
#into(table) ⇒ Object
Specify a table for a SELECT …
-
#quoted_identifier_append(sql, v) ⇒ Object
Access uses [] for quoting identifiers, and can't handle ] inside identifiers.
-
#supports_derived_column_lists? ⇒ Boolean
Access does not support derived column lists.
-
#supports_intersect_except? ⇒ Boolean
Access doesn't support INTERSECT or EXCEPT.
-
#supports_is_true? ⇒ Boolean
Access does not support IS TRUE.
-
#supports_join_using? ⇒ Boolean
Access doesn't support JOIN USING.
-
#supports_multiple_column_in? ⇒ Boolean
Access does not support multiple columns for the IN/NOT IN operators.
-
#truncate ⇒ Object
Access doesn't support truncate, so do a delete instead.
Methods included from EmulateOffsetWithReverseAndCount
#empty?, #select_sql, #supports_offsets_in_correlated_subqueries?
Instance Method Details
#case_expression_sql_append(sql, ce) ⇒ Object
Access doesn't support CASE, so emulate it with nested IIF function calls.
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# File 'lib/sequel/adapters/shared/access.rb', line 93 def case_expression_sql_append(sql, ce) literal_append(sql, ce.with_merged_expression.conditions.reverse.inject(ce.default){|exp,(cond,val)| Sequel::SQL::Function.new(:IIF, cond, val, exp)}) end |
#cast_sql_append(sql, expr, type) ⇒ Object
Access doesn't support CAST, it uses separate functions for type conversion
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# File 'lib/sequel/adapters/shared/access.rb', line 99 def cast_sql_append(sql, expr, type) sql << CAST_TYPES.fetch(type, type).to_s sql << '(' literal_append(sql, expr) sql << ')' end |
#complex_expression_sql_append(sql, op, args) ⇒ Object
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# File 'lib/sequel/adapters/shared/access.rb', line 106 def complex_expression_sql_append(sql, op, args) case op when :ILIKE complex_expression_sql_append(sql, :LIKE, args) when :'NOT ILIKE' complex_expression_sql_append(sql, :'NOT LIKE', args) when :'!=' sql << '(' literal_append(sql, args[0]) sql << ' <> ' literal_append(sql, args[1]) sql << ')' when :'%', :'||' sql << '(' c = false op_str = OPS[op] args.each do |a| sql << op_str if c literal_append(sql, a) c ||= true end sql << ')' when :** sql << '(' literal_append(sql, args[0]) sql << ' ^ ' literal_append(sql, args[1]) sql << ')' when :extract part = args[0] raise(Sequel::Error, "unsupported extract argument: #{part.inspect}") unless format = EXTRACT_MAP[part] sql << "datepart(" << format.to_s << ', ' literal_append(sql, args[1]) sql << ')' else super end end |
#constant_sql_append(sql, constant) ⇒ Object
Use Date(), Now(), and Time() for CURRENT_DATE, CURRENT_TIMESTAMP, and CURRENT_TIME
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# File 'lib/sequel/adapters/shared/access.rb', line 146 def constant_sql_append(sql, constant) case constant when :CURRENT_DATE sql << 'Date()' when :CURRENT_TIMESTAMP sql << 'Now()' when :CURRENT_TIME sql << 'Time()' else super end end |
#cross_join(table) ⇒ Object
Emulate cross join by using multiple tables in the FROM clause.
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# File 'lib/sequel/adapters/shared/access.rb', line 160 def cross_join(table) clone(:from=>@opts[:from] + [table]) end |
#escape_like(string) ⇒ Object
Access uses [] to escape metacharacters, instead of backslashes.
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# File 'lib/sequel/adapters/shared/access.rb', line 165 def escape_like(string) string.gsub(/[\\*#?\[]/){|m| "[#{m}]"} end |
#into(table) ⇒ Object
Specify a table for a SELECT … INTO query.
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# File 'lib/sequel/adapters/shared/access.rb', line 170 def into(table) clone(:into => table) end |
#quoted_identifier_append(sql, v) ⇒ Object
Access uses [] for quoting identifiers, and can't handle ] inside identifiers.
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# File 'lib/sequel/adapters/shared/access.rb', line 176 def quoted_identifier_append(sql, v) sql << '[' << v.to_s << ']' end |
#supports_derived_column_lists? ⇒ Boolean
Access does not support derived column lists.
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# File 'lib/sequel/adapters/shared/access.rb', line 181 def supports_derived_column_lists? false end |
#supports_intersect_except? ⇒ Boolean
Access doesn't support INTERSECT or EXCEPT
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# File 'lib/sequel/adapters/shared/access.rb', line 186 def supports_intersect_except? false end |
#supports_is_true? ⇒ Boolean
Access does not support IS TRUE
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# File 'lib/sequel/adapters/shared/access.rb', line 191 def supports_is_true? false end |
#supports_join_using? ⇒ Boolean
Access doesn't support JOIN USING
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# File 'lib/sequel/adapters/shared/access.rb', line 196 def supports_join_using? false end |
#supports_multiple_column_in? ⇒ Boolean
Access does not support multiple columns for the IN/NOT IN operators
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# File 'lib/sequel/adapters/shared/access.rb', line 201 def supports_multiple_column_in? false end |
#truncate ⇒ Object
Access doesn't support truncate, so do a delete instead.
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# File 'lib/sequel/adapters/shared/access.rb', line 206 def truncate delete nil end |