国产av日韩一区二区三区精品,成人性爱视频在线观看,国产,欧美,日韩,一区,www.成色av久久成人,2222eeee成人天堂

? ??? ??? MySQL ???? mysql float double 部類

mysql float double 部類

Jun 07, 2016 pm 04:27 PM
double float mysql

mysql float double 類型 1.float類型 float列類型默認(rèn)長度查不到結(jié)果，必須指定精度， 比如 num float, insert into table (num) values (0.12); select * from table where num=0.12的話，empty set。 num float(9,7), insert into table (num) values (0.1

mysql float double 類型

1.float類型
float列類型默認(rèn)長度查不到結(jié)果，必須指定精度，
比如 num float, insert into table (num) values (0.12); select * from table where num=0.12的話，empty set。
num float(9,7), insert into table (num) values (0.12); select * from table where num=0.12的話會(huì)查到這條記錄。

mysql> create table tt
-> (
-> num float(9,3)
-> );
Query OK, 0 rows affected (0.03 sec)

mysql> insert into tt(num)values(1234567.8);
ERROR 1264 (22003): Out of range value for column 'num' at row 1
注：超出字段范圍，無法插入

mysql> insert into tt(num)values(123456.8);
Query OK, 1 row affected (0.00 sec)

mysql> select * from tt;
+------------+
| num |
+------------+
| 123456.797 |
+------------+
1 row in set (0.00 sec)
注：小數(shù)位數(shù)不夠，自動(dòng)補(bǔ)齊，但是存在一個(gè)問題就是如上的近似值。

mysql> insert into tt(num)values(123456.867);
Query OK, 1 row affected (0.04 sec)

mysql> select * from tt;
+------------+
| num |
+------------+
| 123456.797 |
| 123456.797 |
| 123456.867 |
+------------+
3 rows in set (0.00 sec)

mysql> select * from tt where num=123456.867;
+------------+
| num |
+------------+
| 123456.867 |
+------------+
1 row in set (0.00 sec)

mysql> insert into tt(num)values(2.8);
Query OK, 1 row affected (0.04 sec)

mysql> select * from tt;
+------------+
| num |
+------------+
| 123456.797 |
| 123456.797 |
| 123456.867 |
| 2.800 |
+------------+
4 rows in set (0.00 sec)

mysql> select * from tt where num=2.8;
+-------+
| num |
+-------+
| 2.800 |
+-------+
1 row in set (0.00 sec)

mysql> insert into tt(num)values(2.888888);
Query OK, 1 row affected (0.00 sec)

mysql> select * from tt;
+------------+
| num |
+------------+
| 123456.797 |
| 123456.797 |
| 123456.867 |
| 2.800 |
| 2.889 |
+------------+
5 rows in set (0.00 sec)
注：小數(shù)位數(shù)超了，自動(dòng)取近似值。

--------------------------------------------------------------------------------------

2.double類型

mysql> create table tt(
-> num double(9,3)
-> );
Query OK, 0 rows affected (0.02 sec)

mysql> insert into tt(num) values(234563.9);
Query OK, 1 row affected (0.00 sec)

mysql> select * from tt;
+------------+
| num |
+------------+
| 234563.900 |
+------------+
1 row in set (0.00 sec)

mysql> insert into tt(num) values(2345623.2);
ERROR 1264 (22003): Out of range value for column 'num' at row 1
mysql> insert into tt(num) values(234563.2);
Query OK, 1 row affected (0.00 sec)

mysql> select * from tt;
+------------+
| num |
+------------+
| 234563.900 |
| 234563.200 |
+------------+
2 rows in set (0.00 sec)

mysql> insert into tt(num) values(2.8);
Query OK, 1 row affected (0.00 sec)

mysql> select * from tt;
+------------+
| num |
+------------+
| 234563.900 |
| 234563.200 |
| 2.800 |
+------------+
3 rows in set (0.00 sec)

FLOAT(M,D)或REAL(M,D)或DOUBLE PRECISION(M,D)。這里，“(M,D)”表示該值一共顯示M位整數(shù)，其中D位位于小數(shù)點(diǎn)后面。
例如，定義為FLOAT(7,4)的一個(gè)列可以顯示為-999.9999。MySQL保存值時(shí)進(jìn)行四舍五入，因此如果在FLOAT(7,4)列內(nèi)插入999.00009，近似結(jié)果是999.0001。

1樓yc73695昨天 15:58
頂一個(gè)啦
? ????? ??
? ?? ??? ????? ???? ??? ??????, ???? ?????? ????. ? ???? ?? ???? ?? ??? ?? ????. ???? ??? ???? ???? ??? ?? admin@php.cn?? ?????.

? AI ??

Undresser.AI Undress

Undresser.AI Undress

???? ?? ??? ??? ?? AI ?? ?

AI Clothes Remover

AI Clothes Remover

???? ?? ???? ??? AI ?????.

Video Face Swap

Video Face Swap

??? ??? AI ?? ?? ??? ???? ?? ???? ??? ?? ????!

???

??? ??

???++7.3.1

???++7.3.1

???? ?? ?? ?? ???

SublimeText3 ??? ??

SublimeText3 ??? ??

??? ??, ???? ?? ????.

???? 13.0.1 ???

???? 13.0.1 ???

??? PHP ?? ?? ??

???? CS6

???? CS6

??? ? ?? ??

SublimeText3 Mac ??

SublimeText3 Mac ??

? ??? ?? ?? ?????(SublimeText3)

???

??? ??

??? ????
1601
29
PHP ????
1502
276
???
PHP? ???? Q & A ???? ???? ???? ?? PHP ?? ? ???? ?? ?? ??? ?? ??? ?? PHP? ???? Q & A ???? ???? ???? ?? PHP ?? ? ???? ?? ?? ??? ?? ??? ?? Jul 23, 2025 pm 07:21 PM

1. PHP ?? ?? ? ?? ?????? Laravel MySQL VUE/React ??? ? ?? ??? ???? ??? ?? ?? ??? ?? Laravel MySQL VUE/React ??? ? ?? ?????. 2. ???? ?? (REDIS), ?????? ???, CDN ? ??? ?? ???????. 3. ?? ???, CSRF ??, HTTPS, ???? ??? ? ?? ??? ??? ???????. 4. ? ??? ??, ?? ??, ??, ???, ?? ?? ? ?? ??? ??? ???? ? ? ??? ??? ?? ????.

PHP ???? ?? ??? ???? ?? PHP ?? ?? ?? ??? ?? ?? PHP ???? ?? ??? ???? ?? PHP ?? ?? ?? ??? ?? ?? Jul 25, 2025 pm 08:33 PM

PHP?? ?? ??? ???? ? ?? ?? ??? ????. 1. php.ini? ?? ??? ??; 2. ? ?? (? : Apache? Setenv ?? nginx? FastCGI_Param)? ??????. 3. PHP ?????? putenv () ??? ??????. ? ??? Php.ini? ????? ??? ???? ??? ???? ? ?? ??? ?? ???? ????? ???? Putenv ()? ?? ??? ?????. ?? ???? ?? ?? (? : php.ini ?? ? ?? ??)? ???? ????. ?? ?? ??? ??? ?? ??? ????? ???? ?? ????.

???? ??? MySQL ??? ?????? ???? ??? MySQL ??? ?????? Jul 20, 2025 am 01:49 AM

MySQL ?? ???? ???? ?? Terraform? ???? ???, Ansible Management ??, ?? ????? GIT ? ?? ? ?? ??? ???? ????. 1. Terraform? ???? ??, ??, ??? ?? ? AWSRD? ?? ??? ??? ?? MySQL ????? ?????. 2. AnsiblePlayBook? ???? ?????? ??? ??, ?? ?? ?? ?? ?? ??? ?????. 3. ?? ?? ??? GIT ??, ?? ?? ?? ? ?? ??? ?????. 4. ?? ?? ? ??? ??? ??? Vault ?? AnsibleVault? ???? ??? ???? ??? ?? ? ?? ?? ??? ??????.

SSL/TLS ???? MySQL ?? ?? SSL/TLS ???? MySQL ?? ?? Jul 21, 2025 am 02:08 AM

SSL/TLS ??? MySQL ??? ??? ??? ?????? ????? ?? ??? ?? ??? ???? ?? ??? ? ???? SSL/TLS? ????? ?? ??? ???? ?? ?? ?? ??? ???? ? ????. 2. MySQL? SSL/TLS? ???? ??? ?????? ???? ?? ?? ???? ssl-ca, ssl-cert ? ssl-key ??? ???? ???? ?? ????? ?? ??? ???????. 3. ?????? ??? ? SSL? ???? ??? ?????? ???? ?? ? ? ?? ??? ???? ??; 4. SSL ???? ?? ???? ?? ???? ??? ?? ??, ??? ?? ?? ? ????? ?? ?? ??? ?????.

PHP? ???? ?? ?? ?? PHP ?? ???? ? ??? ?? ?? ?? PHP? ???? ?? ?? ?? PHP ?? ???? ? ??? ?? ?? ?? Jul 23, 2025 pm 07:00 PM

??? ?? ???? ????? PHP? ?? ??, ??, ?? ? ?? ??? ??????? ?????? ???? ???? ?? ???? ???????. 2. ?? ???? ??? ??? ??? ?? ????????. ???, ?? ???, ?? ?? ?? ?? ??? ??; 3. ?? ?? ???? PHP?? ???? ??? ??? ???? ???? ?? ??? ??? ???? ?? ?? ??? ???? ?? ??? ?????. 4. ?? ??? ???, ??, F1 ? ? CTR, ???? ???? A/B ???? ?? ??? ?????. 5. ?? ??? ??? ?? ??, ??? ?? ??, ?? ?? ?? ? ??? ??? ?? ?? ? ? ????. 6. ?? ??? ???? ?? ? ?? ??, ??? ??, ?? ??? ? SQL ?? ???? ???? ?? ??? ? ??? ??? ?????.

PHP PHP ??? ?? ?? ? ???? AI ??? ?? ???? ???? ?? PHP PHP ??? ?? ?? ? ???? AI ??? ?? ???? ???? ?? Jul 25, 2025 pm 05:54 PM

??? PHP ??? ??? ??? ?? ???? ??? ?? ????? ???????. Laravel? ?? ??? ???? ??? ? ? ???? ??? ??? ???? ?????? ?? ? ?? ?? ???? ?????. Symfony? ? ???? ??? ???? ?????. Codeigniter? ??? ??? ?? ??? ?? ??? ?? ????? ?????. 2. AI ??? ???? ????? ??? ??? ??, ???? ?? ?? (? : ???, ??, F1 ?), ??? ? ?? ?? ? ?? ??? ?? ???? ?? ??? ???? ???? ?? ??? ? ?? ???? ?? ?? ??? ????? ?? ???? ????? ?????? ??? ????? ???????. 3. ??? ?? ?? ????? ?? ??? ?????. AES? ?? ??? ???? ????? ?????.

PHP? ??? ?? ??? ??? ???? ??. PHP ??? ?? ??? ?? ?? PHP? ??? ?? ??? ??? ???? ??. PHP ??? ?? ??? ?? ?? Jul 25, 2025 pm 06:57 PM

PHP? ??? ?? ??, ?????? ???? ? ?? AI ???? ???? ? ????? ??? ?? ????? ??? ? ??? ??? ??? ?????. 2.?? ??? ?? ?? ??? ????? ???????. ??? ??? ??? ???, PHP ??? ??? ? ?? ??? ???? ?? ?? ?? ??? ???? ??? OpenAI ?? DialogFlow? ?? ?? AI ???? ???? ???? ??? ????. 3. ?? ??? ???? ???? ???? ?? PHP? ?? MySQL ? ?? ??????? ?????. 4. ?? AI ???? guzzle? ???? HTTP ??? ??? Apikeys? ???? ???? ?? ?? ? ?? ??? ? ???????. 5. ?????? ????? ??, ???, ?? ?? ? ??? ???? ???????, ???? ????? ???? ?? ? ??? ???? ?? ???? ???????.

PHP ????? ?? ??? ??? ??? ?????? PHP ??? ????? ?? ? CI ?? ?? PHP ????? ?? ??? ??? ??? ?????? PHP ??? ????? ?? ? CI ?? ?? Jul 25, 2025 pm 08:54 PM

PHP ????? ?? ??? ??? ? ??? ??? CI (Continuous Integration) ????? ???? ? ????. 1. DockerFile? ???? ?? ???, ?? ??, ??? ?? ? ?? ??? ???? PHP ??? ?????. 2. Gitlabci? ?? CI/CD ??? ???? .gitlab-ci.yml ??? ?? ??, ??? ? ?? ??? ???? ?? ??, ??? ? ??? ?????. 3. PHPUNIT? ?? ??? ??? ??? ???? ?? ?? ? ???? ???? ????????. 4. Kubernetes? ?? ?? ?? ??? ???? ?? .yaml ??? ?? ?? ??? ?????. 5. Dockerfile ??? ? ??? ??? ??????

See all articles