mysql 使用技巧 分頁limit

InternetJava發表於2020-04-18
mysql 分頁使用 limit關鍵字,limit x,y (x代表從哪條資料開始,y代表頁面大小。mysql第一條資料在limit計算時索引為0)
limit 10
  前10條
limit 0,10
  從第1條開始的10條
limit 10,10
  從第 11 條開始的 10 條
limit 100,10
  從第101條開始的10條
  資料量大時(>千萬),效率低
oracal 分頁,使用 oracle的特殊列 rownum
select * from (select *,rownum R from (select * from a)

例項:查詢入職員工時間排名倒數第三的員工所有資訊。limit 2,1代表選擇從第3條資料開始的1條資料,即第3頁資料,頁面大小為1

select * from employees order by hire_date desc limit 2,1

 

前n條資料,即從索引0開始計算:limit n 或者 limit 0,n

mysql> select * from employees order by hire_date desc limit 5;
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
| employee_id | first_name | last_name | email   | phone_number       | hire_date  | job_id   | salary  | commission_pct | manager_id | department_id |
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
|         173 | Sundita    | Kumar     | SKUMAR  | 011.44.1343.329268 | 2000-04-21 | SA_REP   | 6100.00 |           0.10 |        148 |            80 |
|         167 | Amit       | Banda     | ABANDA  | 011.44.1346.729268 | 2000-04-21 | SA_REP   | 6200.00 |           0.10 |        147 |            80 |
|         166 | Sundar     | Ande      | SANDE   | 011.44.1346.629268 | 2000-03-24 | SA_REP   | 6400.00 |           0.10 |        147 |            80 |
|         128 | Steven     | Markle    | SMARKLE | 650.124.1434       | 2000-03-08 | ST_CLERK | 2200.00 |           NULL |        120 |            50 |
|         165 | David      | Lee       | DLEE    | 011.44.1346.529268 | 2000-02-23 | SA_REP   | 6800.00 |           0.10 |        147 |            80 |
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
5 rows in set (0.00 sec)

mysql> select * from employees order by hire_date desc limit 0,5;
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
| employee_id | first_name | last_name | email   | phone_number       | hire_date  | job_id   | salary  | commission_pct | manager_id | department_id |
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
|         173 | Sundita    | Kumar     | SKUMAR  | 011.44.1343.329268 | 2000-04-21 | SA_REP   | 6100.00 |           0.10 |        148 |            80 |
|         167 | Amit       | Banda     | ABANDA  | 011.44.1346.729268 | 2000-04-21 | SA_REP   | 6200.00 |           0.10 |        147 |            80 |
|         166 | Sundar     | Ande      | SANDE   | 011.44.1346.629268 | 2000-03-24 | SA_REP   | 6400.00 |           0.10 |        147 |            80 |
|         128 | Steven     | Markle    | SMARKLE | 650.124.1434       | 2000-03-08 | ST_CLERK | 2200.00 |           NULL |        120 |            50 |
|         165 | David      | Lee       | DLEE    | 011.44.1346.529268 | 2000-02-23 | SA_REP   | 6800.00 |           0.10 |        147 |            80 |
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
5 rows in set (0.00 sec)

 

更多例子 

limit 5     前5條資料
limit 2,1   第3頁資料,頁面大小為1
limit 2,2   第2頁資料,頁面大小為2
limit 2,3   第3條資料起,共3條資料,此資料不符合分頁資料顯示格式
分頁顯示格式:limit startIndex pageSize
startIndex = (需要查詢的頁碼數 - 1) * pageSize
mysql> select * from employees order by hire_date desc limit 5;
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
| employee_id | first_name | last_name | email   | phone_number       | hire_date  | job_id   | salary  | commission_pct | manager_id | department_id |
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
|         173 | Sundita    | Kumar     | SKUMAR  | 011.44.1343.329268 | 2000-04-21 | SA_REP   | 6100.00 |           0.10 |        148 |            80 |
|         167 | Amit       | Banda     | ABANDA  | 011.44.1346.729268 | 2000-04-21 | SA_REP   | 6200.00 |           0.10 |        147 |            80 |
|         166 | Sundar     | Ande      | SANDE   | 011.44.1346.629268 | 2000-03-24 | SA_REP   | 6400.00 |           0.10 |        147 |            80 |
|         128 | Steven     | Markle    | SMARKLE | 650.124.1434       | 2000-03-08 | ST_CLERK | 2200.00 |           NULL |        120 |            50 |
|         165 | David      | Lee       | DLEE    | 011.44.1346.529268 | 2000-02-23 | SA_REP   | 6800.00 |           0.10 |        147 |            80 |
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
5 rows in set (0.00 sec)

mysql> select * from employees order by hire_date desc limit 2,1;
+-------------+------------+-----------+-------+--------------------+------------+--------+---------+----------------+------------+---------------+
| employee_id | first_name | last_name | email | phone_number       | hire_date  | job_id | salary  | commission_pct | manager_id | department_id |
+-------------+------------+-----------+-------+--------------------+------------+--------+---------+----------------+------------+---------------+
|         166 | Sundar     | Ande      | SANDE | 011.44.1346.629268 | 2000-03-24 | SA_REP | 6400.00 |           0.10 |        147 |            80 |
+-------------+------------+-----------+-------+--------------------+------------+--------+---------+----------------+------------+---------------+
1 row in set (0.00 sec)

mysql> select * from employees order by hire_date desc limit 2,2;
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
| employee_id | first_name | last_name | email   | phone_number       | hire_date  | job_id   | salary  | commission_pct | manager_id | department_id |
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
|         166 | Sundar     | Ande      | SANDE   | 011.44.1346.629268 | 2000-03-24 | SA_REP   | 6400.00 |           0.10 |        147 |            80 |
|         128 | Steven     | Markle    | SMARKLE | 650.124.1434       | 2000-03-08 | ST_CLERK | 2200.00 |           NULL |        120 |            50 |
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
2 rows in set (0.00 sec)

mysql> select * from employees order by hire_date desc limit 2,3;
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
| employee_id | first_name | last_name | email   | phone_number       | hire_date  | job_id   | salary  | commission_pct | manager_id | department_id |
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
|         166 | Sundar     | Ande      | SANDE   | 011.44.1346.629268 | 2000-03-24 | SA_REP   | 6400.00 |           0.10 |        147 |            80 |
|         128 | Steven     | Markle    | SMARKLE | 650.124.1434       | 2000-03-08 | ST_CLERK | 2200.00 |           NULL |        120 |            50 |
|         165 | David      | Lee       | DLEE    | 011.44.1346.529268 | 2000-02-23 | SA_REP   | 6800.00 |           0.10 |        147 |            80 |
+-------------+------------+-----------+---------+--------------------+------------+----------+---------+----------------+------------+---------------+
3 rows in set (0.00 sec)

 

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