I have a table in MySQL with a field that is decimal, length 9, unsigned. I'm using it for prices.
After I insert the data, and query for it, it has all been rounded and the decimal has been removed.
I'm confused as to why.
Troubleshooting tips?
Host: web.com
phpMyAdmin version: 2.11.10.1
MySQL client version: 5.0.95
Decimal type in MySQL has two tuning knobs: precision and scale. You omitted the scale, so it defaults to 0.
Documentation (link)
The declaration syntax for a DECIMAL column is DECIMAL(M,D). The ranges of values for the arguments in MySQL 5.1 are as follows:
M is the maximum number of digits (the precision). It has a range of 1 to 65. (Older versions of MySQL permitted a range of 1 to 254.)
D is the number of digits to the right of the decimal point (the scale). It has a range of 0 to 30 and must be no larger than M.
Example
mysql> create table test01 (field01 decimal(9));
Query OK, 0 rows affected (0.01 sec)
mysql> insert into test01 (field01) values (123.456);
Query OK, 1 row affected, 1 warning (0.00 sec)
mysql> select * from test01;
+---------+
| field01 |
+---------+
| 123 |
+---------+
1 row in set (0.00 sec)
mysql> create table test02 (field01 decimal(9, 4));
Query OK, 0 rows affected (0.00 sec)
mysql> insert into test02 (field01) values (123.456);
Query OK, 1 row affected (0.01 sec)
mysql> select * from test02;
+----------+
| field01 |
+----------+
| 123.4560 |
+----------+
1 row in set (0.00 sec)
I had the same problem. Turns out PHPMyAdmin ignores the decimal place if you enter and assumes it to be 0.
Use alter table query to change it.
ALTER TABLE tablename CHANGE rate rate DECIMAL(30,3) UNSIGNED NOT NULL;
THe rounding is done because may be you have set its datatype as int.
Change its datatype to double OR Float.
This will help you out.
EDIT
If you are having datatype decimal give its size like this edit.
create table numbers (a decimal(10,2));
The rounding is happening because you need to declare the precision in the type declaration
create table test01 (field01 decimal(9,2));
In PHP/MySQLAdmin go to the Structure of the table, hit change and then set the length (which defaults to 10,0) to 10,2 for financial data (dollars).
Related
I've been trying to save the product weight in a database field table with the type of decimal.
My code:
$p = Product::find($id)->update([
'weight' => $product['weight'] ? floatval($product['weight']) : null,
]);
It always rounds up the number for some reason, even though dd(floatval($product['weight'])) outputs the correct value, when i try to save it it doesn't save the correct value, only changing the field to the type of float works, but i read that it is not a correct approach.
I'm using MySQL and the Laravel 8.75.
Decimal type in MySQL has two tuning knobs: precision and scale. You omitted the scale, so it defaults to 0.
Documentation (link)
The declaration syntax for a DECIMAL column is DECIMAL(M,D). The ranges of values for the arguments in MySQL 5.1 are as follows:
M is the maximum number of digits (the precision). It has a range of 1 to 65. (Older versions of MySQL permitted a range of 1 to 254.)
D is the number of digits to the right of the decimal point (the scale). It has a range of 0 to 30 and must be no larger than M.
Example
mysql> create table test01 (field01 decimal(9));
Query OK, 0 rows affected (0.01 sec)
mysql> insert into test01 (field01) values (123.456);
Query OK, 1 row affected, 1 warning (0.00 sec)
mysql> select * from test01;
+---------+
| field01 |
+---------+
| 123 |
+---------+
1 row in set (0.00 sec)
mysql> create table test02 (field01 decimal(9, 4));
Query OK, 0 rows affected (0.00 sec)
mysql> insert into test02 (field01) values (123.456);
Query OK, 1 row affected (0.01 sec)
mysql> select * from test02;
+----------+
| field01 |
+----------+
| 123.4560 |
+----------+
1 row in set (0.00 sec)
Probably modifying the column with a migration
Schema::table('products', function (Blueprint $table) {
$table->decimal('weight', 9, 4)->change();
});
Documentation
I have a BLOB field in a MySQL database that contains a seven bit binary field - in essence, one bit for each day of the week, starting on a Sunday with the right hand bit.
I have two records, on one the binary field (called Flags) is set to 0101000 while the other is set to 0000010. I use Querious software on a Mac for database work, and that shows that the field does contain binary data and confirms the above entries.
However, when I issue a SELECT statement, that includes Flags & 8 = 8 in the WHERE statement, both records are returned, yet I believe only the first should be.
The PHP code using bindec($data->flags) & 8 correctly only marks the first record as having the 4th bit (i.e. value 8) set.
Can anyone advise what I'm doing wrong with the MySQL statement - i've been looking at this for over 36 hours now, and just cant see it.
Seems to work in fine here here (on v5.7.13)
mysql> create table z (x bit(7));
Query OK, 0 rows affected (0.02 sec)
mysql> insert into z (x) values (0b0101000), (0b000010);
Query OK, 2 rows affected (0.01 sec)
Records: 2 Duplicates: 0 Warnings: 0
mysql> select cast(x & 8 as unsigned) from z;
+-------------------------+
| cast(x & 8 as unsigned) |
+-------------------------+
| 8 |
| 0 |
+-------------------------+
2 rows in set (0.00 sec)
mysql> select x, cast(x as unsigned) from z where x & 8;
+------+---------------------+
| x | cast(x as unsigned) |
+------+---------------------+
| ( | 40 |
+------+---------------------+
1 row in set (0.00 sec)
You should show your ACTUAL query.
I am using int(22) for now as my table field. but for now it's overflow with value 2147483647 and stop so my 3000 field gone the same id. I am really stuck with that
For now i changed it with bigint(20) unsigned but may be i will come same condition in future.
Please advice me what will be better use for this
varchar or bigint or any
Also would be great if i get some explanation.
Think of it this way: how long did it take you to fill up an INT? Perhaps six months?
Now multiply that time by roughly 4 billion.
That's how long it will take to fill up a BIGINT, if you insert data at the same rate. So if it took you half a year to fill an INT, the BIGINT will last 2 billion years.
That gives you some scope of how much larger the range of a BIGINT is than an INT. A BIGINT supports up to 264 values, which is 232 times larger than the number of values in an INT.
NUMERIC can store 65 digits which is larger than BIGINT UNSINGED
mysql> create table integral (a bigint, b numeric(65,0));
Query OK, 0 rows affected (0.06 sec)
mysql> insert into integral (a) values(123456789012345678901234567890);
Query OK, 1 row affected, 1 warning (0.01 sec)
mysql> show warnings;
+---------+------+--------------------------------------------+
| Level | Code | Message |
+---------+------+--------------------------------------------+
| Warning | 1264 | Out of range value for column 'a' at row 1 |
+---------+------+--------------------------------------------+
1 row in set (0.00 sec)
mysql> insert into integral (b) values(123456789012345678901234567890);
Query OK, 1 row affected (0.00 sec)
I have a column of type integer with length 10:
`some_number` int(10) unsigned NOT NULL
Into this column I insert a number that is too long:
$some_number = 715988985123857;
$query = "INSERT INTO this_table SET some_number = ?";
$stmt = $mysqli->prepare($query);
$stmt->bind_param('i', $some_number);
$stmt->execute();
When I look at what is in the table, the number is now:
2147483647
How and why did 715988985123857turn into 2147483647?
Why didn't it get truncated?
What is the mechanism behind this transformation, and can the resulting number be calculated with some formula?
I'm not looking for a solution. I just want to understand the specific number.
http://dev.mysql.com/doc/refman/5.0/en/integer-types.html
The integer overflow will set the max allowed number in the DB as
2147483647
So you need bigint datatype for storing bigger integer
How and why did 715988985123857turn into 2147483647?
Why didn't it get truncated?
What is the mechanism behind this transformation, and can the resulting number be calculated with some formula?
The behavior depends on MySQL Strict SQL Mode setting:
Strict mode controls how MySQL handles invalid or missing values in data-change statements such as INSERT or UPDATE.
There is a chapter in MySQL manual explaining how MySQL handles out-of-range values: Out-of-Range and Overflow Handling:
[...] If no restrictive modes are enabled, MySQL clips the value to the appropriate endpoint of the range and stores the resulting value instead.
In case of Integer Type, the maximum value is:
2147483647 for signed type
4294967295 for unsigned type
Since your query did not throw error, but instead, the column got updated with max allowed value, you can assume that Strict SQL Mode is not enabled on your server. You can verify that by running:
SELECT ##GLOBAL.sql_mode;
SELECT ##SESSION.sql_mode;
None of them will contain STRICT_TRANS_TABLES nor STRICT_ALL_TABLES values (more about the values in MySQL man: sql_mode).
Take this example to test the different behaviors between modes:
mysql> create table test_sql_mode(id int);
mysql> set sql_mode = 'STRICT_TRANS_TABLES';
mysql> SELECT ##SESSION.sql_mode;
+---------------------+
| ##SESSION.sql_mode |
+---------------------+
| STRICT_TRANS_TABLES |
+---------------------+
1 row in set (0.00 sec)
mysql> insert into test_sql_mode(id) value(123456789123456789);
ERROR 1264 (22003): Out of range value for column 'id' at row 1
mysql> select * from test_sql_mode;
Empty set (0.00 sec)
mysql> set sql_mode = '';
mysql> SELECT ##SESSION.sql_mode;
+--------------------+
| ##SESSION.sql_mode |
+--------------------+
| |
+--------------------+
1 row in set (0.00 sec)
mysql> insert into test_sql_mode(id) value(123456789123456789);
Query OK, 1 row affected, 1 warning (0.05 sec)
mysql> show warnings;
+-------+------+---------------------------------------------+
| Level | Code | Message |
+-------+------+---------------------------------------------+
| Error | 1264 | Out of range value for column 'id' at row 1 |
+-------+------+---------------------------------------------+
mysql> select * from test_sql_mode;
+------------+
| id |
+------------+
| 2147483647 |
+------------+
1 row in set (0.00 sec)
In short, with strict mode out-of-range value produces an error, without - the value gets adjusted to the allowed limit and a warning is produced.
As for this question:
can the resulting number be calculated with some formula?
I'm not aware of any simple and pure MySQL formula. You would have to check the data type and length:
select data_type, numeric_precision, numeric_scale
from information_schema.columns
where table_schema = "test_database"
and table_name = "test_sql_mode"
and column_name = "id"
...and based on that determine allowed limit.
Non-sql? Data validation (server- and client-side) is the solution.
Well as far as i know, it doesn't have anything to do with PHP, bcx.
If PHP encounters a number beyond the bounds of the integer type, it will be interpreted as a float instead.
Also, an operation which results in a number beyond the bounds of the integer type will return a float instead.
So it will be the functionality of SQL which changes the value.
i have an existing mysql table with the id column defined as primary, and auto-increment set as true. now, i would like to know if i can set the auto-increment to start from a predefined value, say 5678, instead of starting off from 1.
I would also like to know if i can set the steps for auto-incrementing, say increase by 15 each for each new record insertion (instead of the default increment value of 1).
Note- i am using phpmyadmin to play with the db, and i have many tables but only one db.
Thanks.
ALTER TABLE tbl AUTO_INCREMENT = 5678 will set the auto increment to 5678 for that table. Have a look at the detailed information here.
You can set the auto increment value using below command
ALTER TABLE tbl_name AUTO_INCREMENT = 5678;
And can update the auto_increment counter variable using below command
SET ##auto_increment_increment=15;
Loo at here for more info
mysql> SET ##auto_increment_increment=15;
Query OK, 0 rows affected (0.00 sec)
mysql> INSERT INTO autoinc1 VALUES (NULL), (NULL), (NULL), (NULL);
Query OK, 4 rows affected (0.00 sec)
Records: 4 Duplicates: 0 Warnings: 0
mysql> SELECT col FROM autoinc1;
+-----+
| col |
+-----+
| 1 |
| 16 |
| 31 |
| 46 |
You can also use the server-system-variables:
auto_increment_increment
and
auto_increment_offset
This will allow you to increase the offset by other values than 1 (e.g. 15) each time.
If you start from a different value using the same offset on a different server. This will allow you to keep tables on different servers that can be merged without keys overlapping.
e.g.
(inc = 15 offset = 1) (inc=15 offset = 2)
table1 on server A table1 on server B
-----------------------------------------------------
id name id name
1 bill 2 john
16 monica 17 claire
....
This can be very useful.
Because the main usage is to have the same table on different servers behave in a different way, it is a server setting and not a table setting.
ALTER TABLE whatever AUTO_INCREMENT=5678 - alternatively in phpMyAdmin, go to the "Operations" tab of the table view and set it there. For the increment step, use the setting auto_increment_increment.
You can see the example here..
http://pranaydac08.blogspot.in/2013/10/how-set-auto-increment-value-start-from.html