# 记录数量 count ~~~ # 函数原型 public function count($strField = '*', $sAlias = 'row_count') # SELECT COUNT(`test`.*) AS row_count FROM `test` database::table ( 'test' ) ->count() ->getAll (); ~~~ # 平均值 avg ~~~ # 函数原型 public function avg($strField, $sAlias = 'avg_value') # SELECT AVG(`test`.`id`) AS avg_value FROM `test` database::table ( 'test' ) ->avg('id') ->getAll (); # SELECT AVG(`test`.`num1`*`test`.`num2`) AS avg_value FROM `test` database::table ( 'test' ) ->avg('{[num1]*[num2]}') ->getAll (); ~~~ # 最大值 max ~~~ # 函数原型 public function max($strField, $sAlias = 'max_value') # SELECT MAX(`test`.`num`) AS max_value FROM `test` database::table ( 'test' ) ->max('num') ->getAll (); ~~~ # 最小值 min ~~~ # 函数原型 public function min($strField, $sAlias = 'min_value') # SELECT MIN(`test`.`num`) AS min_value FROM `test` database::table ( 'test' ) ->min('num') ->getAll (); ~~~ # 合计 sum ~~~ # 函数原型 public function sum($strField, $sAlias = 'sum_value') # SELECT SUM(`test`.`num`) AS sum_value FROM `test` database::table ( 'test' ) ->sum('num') ->getAll (); ~~~