@@ -43,67 +43,77 @@ def rollback_to_savepoint
4343 end
4444
4545 def add_limit_offset! ( sql , options )
46- # Validate and/or convert integers for :limit and :offets options.
47- if options [ :offset ]
48- raise ArgumentError , "offset should have a limit" unless options [ :limit ]
49- unless options [ :offset ] . kind_of? ( Integer )
50- if options [ :offset ] =~ /^\d +$/
51- options [ :offset ] = options [ :offset ] . to_i
52- else
53- raise ArgumentError , "offset should be an integer"
54- end
55- end
56- end
57- if options [ :limit ] && !( options [ :limit ] . kind_of? ( Integer ) )
58- if options [ :limit ] =~ /^\d +$/
59- options [ :limit ] = options [ :limit ] . to_i
60- else
61- raise ArgumentError , "limit should be an integer"
62- end
63- end
64- # The business of adding limit/offset
65- if options [ :limit ] and options [ :offset ]
66- tally_sql = "SELECT count(*) as TotalRows from (#{ sql . sub ( /\b SELECT(\s +DISTINCT)?\b /i , "SELECT#{ $1} ) }
67- add_lock! tally_sql , options
68- total_rows = select_value ( tally_sql ) . to_i
69- if ( options [ :limit ] + options [ :offset ] ) >= total_rows
70- options [ :limit ] = ( total_rows - options [ :offset ] >= 0 ) ? ( total_rows - options [ :offset ] ) : 0
71- end
72- # Make sure we do not need a special limit/offset for association limiting. http://gist.github.com/25118
73- add_limit_offset_for_association_limiting! ( sql , options ) and return if sql_for_association_limiting? ( sql )
74- # Wrap the SQL query in a bunch of outer SQL queries that emulate proper LIMIT,OFFSET support.
75- sql . sub! ( /^\s *SELECT(\s +DISTINCT)?/i , "SELECT * FROM (SELECT TOP #{ options [ :limit ] } #{ $1} #{ options [ :limit ] + options [ :offset ] } )
76- sql << ") AS tmp1"
77- if options [ :order ]
78- order = options [ :order ] . split ( ',' ) . map do |field |
79- order_by_column , order_direction = field . split ( " " )
80- order_by_column = quote_column_name ( order_by_column )
81- # Investigate the SQL query to figure out if the order_by_column has been renamed.
82- if sql =~ /#{ Regexp . escape ( order_by_column ) } \d +_r\d +)/
83- # Fx "[foo].[bar] AS t4_r2" was found in the SQL. Use the column alias (ie 't4_r2') for the subsequent orderings
84- order_by_column = $1
85- elsif order_by_column =~ /\w +\. \[ ?(\w +)\] ?/
86- order_by_column = $1
87- else
88- # It doesn't appear that the column name has been renamed as part of the query. Use just the column
89- # name rather than the full identifier for the outer queries.
90- order_by_column = order_by_column . split ( '.' ) . last
91- end
92- # Put the column name and eventual direction back together
93- [ order_by_column , order_direction ] . join ( ' ' ) . strip
94- end . join ( ', ' )
95- sql << " ORDER BY #{ change_order_direction ( order ) } #{ order }
96- else
97- sql << ") AS tmp2"
98- end
99- elsif options [ :limit ] && sql !~ /^\s *SELECT (@@|COUNT\( )/i
100- if md = sql . match ( /^(\s *SELECT)(\s +DISTINCT)?(.*)/im )
101- sql . replace "#{ md [ 1 ] } #{ md [ 2 ] } #{ options [ :limit ] } #{ md [ 3 ] }
102- else
103- # Account for building SQL fragments without SELECT yet. See #update_all and #limited_update_conditions.
104- sql . replace "TOP #{ options [ :limit ] } #{ sql }
105- end
46+ limit = options [ :limit ]
47+ offset = options [ :offset ]
48+
49+
50+ if limit && !offset
51+ sql
52+ elsif limit || offset
53+ sql
10654 end
55+
56+ # options[:offset] ||= 0
57+ # if options[:offset] > 0
58+ # options[:order] ||= if order_by = sql.match(/ORDER BY (.*$)/i)
59+ # order_by[1]
60+ # else
61+ # table_name = sql.match('FROM ([\[\]a-zA-Z0-9_\.]+)')[1]
62+ #
63+ # find_table_primary_key_columns(table_name)
64+ # end
65+ # sql.sub!(/ORDER BY.*$/i, '')
66+ # sql.sub!(/SELECT/i, "SELECT * FROM ( SELECT ROW_NUMBER() OVER( ORDER BY #{options[:order] } ) AS row_num, ")
67+ # sql << ") AS t WHERE row_num > #{options[:offset]}"
68+ # end
69+ # sql.sub!(/^SELECT/i, "SELECT TOP #{options[:limit]}") if options[:limit]
70+ # sql
71+
72+
73+
74+ # # The business of adding limit/offset
75+ # if options[:limit] and options[:offset]
76+ # tally_sql = "SELECT count(*) as TotalRows from (#{sql.sub(/\bSELECT(\s+DISTINCT)?\b/i, "SELECT#{$1} TOP 1000000000")}) tally"
77+ # add_lock! tally_sql, options
78+ # total_rows = select_value(tally_sql).to_i
79+ # if (options[:limit] + options[:offset]) >= total_rows
80+ # options[:limit] = (total_rows - options[:offset] >= 0) ? (total_rows - options[:offset]) : 0
81+ # end
82+ # # Make sure we do not need a special limit/offset for association limiting. http://gist.github.com/25118
83+ # add_limit_offset_for_association_limiting!(sql,options) and return if sql_for_association_limiting?(sql)
84+ # # Wrap the SQL query in a bunch of outer SQL queries that emulate proper LIMIT,OFFSET support.
85+ # sql.sub!(/^\s*SELECT(\s+DISTINCT)?/i, "SELECT * FROM (SELECT TOP #{options[:limit]} * FROM (SELECT#{$1} TOP #{options[:limit] + options[:offset]}")
86+ # sql << ") AS tmp1"
87+ # if options[:order]
88+ # order = options[:order].split(',').map do |field|
89+ # order_by_column, order_direction = field.split(" ")
90+ # order_by_column = quote_column_name(order_by_column)
91+ # # Investigate the SQL query to figure out if the order_by_column has been renamed.
92+ # if sql =~ /#{Regexp.escape(order_by_column)} AS (t\d+_r\d+)/
93+ # # Fx "[foo].[bar] AS t4_r2" was found in the SQL. Use the column alias (ie 't4_r2') for the subsequent orderings
94+ # order_by_column = $1
95+ # elsif order_by_column =~ /\w+\.\[?(\w+)\]?/
96+ # order_by_column = $1
97+ # else
98+ # # It doesn't appear that the column name has been renamed as part of the query. Use just the column
99+ # # name rather than the full identifier for the outer queries.
100+ # order_by_column = order_by_column.split('.').last
101+ # end
102+ # # Put the column name and eventual direction back together
103+ # [order_by_column, order_direction].join(' ').strip
104+ # end.join(', ')
105+ # sql << " ORDER BY #{change_order_direction(order)}) AS tmp2 ORDER BY #{order}"
106+ # else
107+ # sql << ") AS tmp2"
108+ # end
109+ # elsif options[:limit] && sql !~ /^\s*SELECT (@@|COUNT\()/i
110+ # if md = sql.match(/^(\s*SELECT)(\s+DISTINCT)?(.*)/im)
111+ # sql.replace "#{md[1]}#{md[2]} TOP #{options[:limit]}#{md[3]}"
112+ # else
113+ # # Account for building SQL fragments without SELECT yet. See #update_all and #limited_update_conditions.
114+ # sql.replace "TOP #{options[:limit]} #{sql}"
115+ # end
116+ # end
107117 end
108118
109119 def empty_insert_statement_value
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