The text data I have for a column in database in an enterprise application (uses hibernate) is huge and after increasing varchar size to a specific number, I don't have any other choice but to change the datatype to text. Can anyone help me understand how it may affect my application. Do I need to take care of anything else or just changing the datatype works ?
You should use TEXT. Although, that's the same thing as VARCHAR:
If the declared type of the column contains any of the strings "CHAR",
"CLOB", or "TEXT" then that column has TEXT affinity. Notice that the
type VARCHAR contains the string "CHAR" and is thus assigned TEXT
affinity
Also note
Note that numeric arguments in parentheses that following the type
name (ex: "VARCHAR(255)") are ignored by SQLite - SQLite does not
impose any length restrictions (other than the large global
SQLITE_MAX_LENGTH limit) on the length of strings, BLOBs or numeric
values.
Your application work fine with datatype text.You don't need to take care of any thing
if you want to be sure, create backup database first just in case,
or at least backup/duplicate table you were going to make changes
for me I also prefer varchar than text
because varchar used to be using smaller memory than text
ex : address (100) , records only using 80 character, will be saved as 80 character in varchar
while in text , will be saved as 100 character
I've written a MySQL script to create a database for hypothetical hospital records and populate it with data. One of the tables, Department, has a column named Description, which is declared as type varchar(200). When executing the INSERT command for Description I get an error:
error 1406: Data too long for column 'Description' at row 1.
All the strings I'm inserting are less than 150 characters.
Here's the declaration:
CREATE TABLE Department(
...
Description varchar(200)
...);
And here's the insertion command:
INSERT INTO Department VALUES
(..., 'There is some text here',...), (..., 'There is some more text over here',...);
By all appearances, this should be working. Anyone have some insight?
Change column type to LONGTEXT
I had a similar problem when migrating an old database to a new version.
Switch the MySQL mode to not use STRICT.
SET ##global.sql_mode= 'NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION';
Error Code: 1406. Data too long for column - MySQL
There is an hard limit on how much data can be stored in a single row of a mysql table, regardless of the number of columns or the individual column length.
As stated in the OFFICIAL DOCUMENTATION
The maximum row size constrains the number (and possibly size) of columns because the total length of all columns cannot exceed this size. For example, utf8 characters require up to three bytes per character, so for a CHAR(255) CHARACTER SET utf8 column, the server must allocate 255 × 3 = 765 bytes per value. Consequently, a table cannot contain more than 65,535 / 765 = 85 such columns.
Storage for variable-length columns includes length bytes, which are assessed against the row size. For example, a VARCHAR(255) CHARACTER SET utf8 column takes two bytes to store the length of the value, so each value can take up to 767 bytes.
Here you can find INNODB TABLES LIMITATIONS
in mysql if you take VARCHAR then change it to TEXT bcoz its size is 65,535
and if you can already take TEXT the change it with LONGTEXT only if u need more then 65,535.
total size of LONGTEXT is 4,294,967,295 characters
Varchar has its own limits. Maybe try changing datatype to text.!
Turns out, as is often the case, it was a stupid error on my part. The way I was testing this, I wasn't rebuilding the Department table after changing the data type from varchar(50) to varchar(200); I was just re-running the insert command, still with the column as varchar(50).
If your source data is larger than your target field and you just want to cut off any extra characters, but you don't want to turn off strict mode or change the target field's size, then just cut the data down to the size you need with LEFT(field_name,size).
INSERT INTO Department VALUES
(..., LEFT('There is some text here',30),...), (..., LEFT('There is some more text over here',30),...);
I used "30" as an example of your target field's size.
In some of my code, it's easy to get the target field's size and do this. But if your code makes that hard, then go with one of the other answers.
For me, I defined column type as BIT (e.g. "boolean")
When I tried to set column value "1" via UI (Workbench), I was getting a "Data too long for column" error.
Turns out that there is a special syntax for setting BIT values, which is:
b'1'
With Hibernate you can create your own UserType. So thats what I did for this issue. Something as simple as this:
public class BytesType implements org.hibernate.usertype.UserType {
private final int[] SQL_TYPES = new int[] { java.sql.Types.VARBINARY };
//...
}
There of course is more to implement from extending your own UserType but I just wanted to throw that out there for anyone looking for other methods.
Very old question, but I tried everything suggested above and still could not get it resolved.
Turns out that, I had after insert/update trigger for the main table which tracked the changes by inserting the record in history table having similar structure. I increased the size in the main table column but forgot to change the size of history table column and that created the problem.
I did similar changes in the other table and error is gone.
I try to create a table with a field as 200 characters and I've added two rows with early 160 characters and it's OK. Are you sure your rows are less than 200 characters?
Show SqlFiddle
There was a similar problem when storing a hashed password into a table. Changing the maximum column length didn't help. Everything turned out to be simple. It was necessary to delete the previously created table from the database, and then test the code with new values of the allowable length.
If you re using type: DataTypes.STRING, then just pass how long this string can be like DataTypes.STRING(1000)
In my case this error occurred due to entering data a wrong type for example: if it is a long type column, i tried to enter in string type. so please check your data that you are entering and type are same or not
For me, I try to update column type "boolean" value
When I tried to set column value 1 MySQL Workbench, I was getting a "Data too long for column" error.
So for that there is a special syntax for setting boolean values, which is:
UPDATE `DBNAME`.`TABLE_NAME` SET `FIELD_NAME` = false WHERE (`ID` = 'ID_VALUE'); //false for 0
UPDATE `DBNAME`.`TABLE_NAME` SET `FIELD_NAME` = true WHERE (`ID` = 'ID_VALUE'); //true for 1
I had a different problem which gave the same error so I'll make a quick recap as this seems to have quite different sources and the error does not help much to track down the root cause.
Common sources for INSERT / UPDATE
Size of value in row
This is exactly what the error is complaining about. Maybe it's just that.
You can:
increase the column size: for long strings you can try to use TEXT, MEDIUMTEXT or LONGTEXT
trim the value that is too long: you can use tools from the language you're using to build the query or directly in SQL with LEFT(value,size) or RIGHT(...) or SUBSTRING(...)
Beware that there is a maximum row size in a MySQL table as reported by this answer. Check documentation and InnoDB engine limitations.
Datatype Mismatch
One or more rows are of the wrong datatype.
common sources of error are
ENUM
BIT: don't use 1 but b'1'
Data outlier
In a long list of insert one can easily miss a row which has a field not adhering to the column typing, like an ENUM generated from a string.
Python Django
Check if you have sample_history enabled, after a change in a column size it must be updated too.
I am going to store URLs inside of my database and I just had a simple question. Do URLs have to be a certain data type?
Simply put the data type should be VARCHAR
URLs can contain any number of characters, and can be any length (within reason on the smaller end). A CHAR field can only contain the number of characters that is set in the table definition. A VariableCharacter (VARCHAR) field can contain a variable number of characters. So since not all URL's are of equal length you need the variability. You could make an argument to use a TEXT field if you needed to store really long URLs; however, for most use cases VARCHAR will suffice.
An url has special, numerically and normal chars.
Therefor you should use the type "VARCHAR" in MySql.
I have a MySQL column "phone" , and when data comes from my php form, if there's a zero at the beginning, it will disappear in the table, for example :
"06719823" becomes "6719823"
I first though it was a problem from php, cause I'm using mysql_real_escape_string(), but then I tried to modify the SQL field directly on phpmyadmin, and I can't add a first 0, it always delete it.
Colonne Type Interclassement Attributs Null Défaut Extra
phone int(10) Oui NULL
What's wrong ? Should I assign an "interclassement" utf8_general_ci ?
Change your column type to char(10) for 10 digit phone numbers.
If the column type is int (integer), the number will be internally represented as an integer, meaning "first 0s" won't be stored, as they hold no meaning for integers.
Since what you are actually trying to store has meaning as a sequence of characters, and not as a quantity, it would make more sense to store it as a char(n), for n-digit sequences, or as a varchar for sequences whose size varies a lot.
Make your phone attribute as Varchar or Text to avoid this.
Phone numbers can at time also contain brackets and hyphens plus you can avoid your problem as well.
Change your data type. Int Data type will not store the starting 0's.
You can try as suggested above char or varchar
Integers : 06719823 = 6719823 = 0006719823
Save the phone as varchar if you would like to retain zeros in the begining
I need to create a good/neutral/bad field. which one would be the more understandable/correct way.
A binary field with null (1=good, null=neutral, 0=bad)
An int (1=good, 2=neutral, 3=bad)
An enum (good, neutral, bad)
Any other
It's only and informative field and I will not need to search by this.
NULL values should be reserved for either:
unknown values; or
not-applicable values;
neither of which is the case here.
I would simply store a CHAR value myself, one of the set {'G','N','B'}. That's probably the easiest solution and takes up little space while still providing mnemonic value (easily converting 'G' to 'Good' for example).
If you're less concerned about space, then you could even store them as varchar(7) or equivalent and store the actual values {'Good','Neutral','Bad'} so that no translation at all would be needed in your select statements (assuming those are the actual values you will be printing).
In Mysql you ought to be using an enum type. You can pick any names you like without worrying about space, because Mysql stores the data as a short integer. See 10.4.4. The ENUM Type in the documentation.