1、p簡單數據記錄查詢p條件數據記錄查詢p排序數據記錄查詢p限制數據記錄查詢數量p統計函數和分組數據記錄查詢查詢所有字段數據Select * from table_name等效查詢Select allfield from table_name查詢指定字段數據SELECT field1 field2 fieldn FROM table_nameSELECT field2 field1 fieldn FROM table_name避免重復數據查詢DISTINCTSELECT field1 field2 fieldn FROM table_nameSELECT field2 field1 fieldn

2、FROM table_name實現數學四則運算數據查詢SELECT 1+1Select filed1*2設置顯示格式數據查詢SELECT CONCAT(ename,雇員的年薪為：,sal*12) yearsalary FROM t_employee;帶有關系運算符和邏輯運算符的條件數據查詢。Select col from table_name where a=b and c1 or d12帶BETWEEN AND關鍵字的條件數據查詢。SELECT field1 field2 fieldn FROM table_name WHERE field BETWEEN VALUE1 AND VALUE2

3、帶IS NULL關鍵字的條件數據查詢。SELECT field1 field2 fieldn FROM table_name WHERE field IS NULL;帶IN關鍵字的條件數據查詢。SELECT field1 field2 fieldn FROM table_name WHERE field IN (value1,value2,value3,valuen);帶LIKE關鍵字的條件數據查詢“_”通配符，該通配符值能匹配單個字符。“%”通配符，該通配符值可以匹配任意長度的字符串，即可以是0個字符，1個字符，也可以很多個字符。Show variables like %gen%;SELEC

4、T field1 field2 fieldn FROM table_name WHERE field LIKE value;SELECT field1 field2 fieldn FROM table_name WHERE CONDITION ORDER BY fileldm1 ASC|DESC,fileldm2 ASC|DESC,SELECT field1 field2 fieldn FROM table_name WHERE CONDITION LIMIT OFFSET_START,ROW_COUNTCOUNT()函數：該統計函數實現統計表中記錄的條數。AVG()函數：該統計函數實現計算字

5、段值的平均值。SUM()函數：該統計函數實現計算字段值的總和。MAX()函數：該統計函數實現查詢字段值的最大值。MIN()函數：該統計函數實現查詢字段值的最小值。SELECT function() FROM table_name WHERE CONDITION GROUP BY field;SELECT GROUP_CONCAT(field) FROM table_name WHERE CONDITION GROUP BY field;SELECT GROUP_CONCAT(field),function(field) FROM table_name WHERE CONDITION GROUP BY field1,field2,fileldn;SELECT function(field)