![]() ![]() Of course, a BCD is more compact in bits than is the equivalent text, but it's a long time since I've heard anyone worry about that amount of storage distinction. Thus a BCD gets used just for holding digits - and that there are code libraries ready for calculating with them is a moot point. The 20 in INT (20) and BIGINT (20) means almost nothing. MySQL supports the SQL standard integer types INTEGER (or INT) and SMALLINT. That means 2 32 values in an INT and 2 64 values in a BIGINT. unsigned int does not allow negative numbers so by default it need only display size 10. For example, there are many situations where something like DECIMAL(18,0) will be used for an ID value, which is numeric but never actually used as a number - i.e. They each accept no more and no fewer values than can be stored in their respective number of bytes. int value can be -2147483648 these are 11 digits so the default display size is 11. ![]() I suspect a reality is that the "data" world has always been a bit slapdash about data formats. I feel I've known about binary-coded-decimal (BCD) formats for longer than I've done data work, but I really can't recall where from - FORTRAN IV perhaps? It probably doesn't occur to me to expect "integer" data types to have consistency across SQL/relational engines and that I would always use DECIMAL for reliable migrations. Signed value - Variables with signed numerals can store 0, positive, and negative numbers. Interesting, not that I use MySQL anywhere. Difference between Signed and Unsigned in MySQL. This optional display width may be used by applications to display integer values having. For example, INT (4) specifies an INT with a display width of four digits. MySQL supports INT/INTEGER data types including synonym INT4. MySQL supports an extension for optionally specifying the display width of integer data types in parentheses following the base keyword for the type. If you want to change from int to tinyint, it is possible to do so without Laravel syntax, but using alter table. INT/INTEGER UNSIGNED, Signed: -231 to 231-1 (2 Gb), Unsigned: 0 to 232-1 (4 Gb). So, if you use int or bigint, it is OK to default length. In fact, I also suffered from unnecessary errors. ![]() If you can't do the opposite, it means that the rollback doesn't work properly, so you should avoid it. mysql> create table mytable (id int unsigned autoincrement primary key) mysql> insert into mytable (id) values (DEFAULT) Query OK, 1 row affected (0. CREATE PROCEDURE luser (in vuserid int unsigned) BEGIN START TRANSACTION DELETE FROM usertable1 WHERE userid vuserid DELETE FROM usertable2. It just describes how much digits shall be shown, but it's always an int with 4 bytes. To modify a timestamp column type a Doctrine type must be registered. I removed the (10) just because it's irrelevant. The following column types can be modified: bigInteger, binary, boolean, date, dateTime, dateTimeTz, decimal, integer, json, longText, mediumText, smallInteger, string, text, time, unsignedBigInteger, unsignedInteger, unsignedSmallInteger, and uuid. When I looked it up, I found something like this.ĭatabase: Migrations - Laravel - The PHP Framework For Web Artisans "If you use int in MySQL, it will always be" int (11) ", but that's just the way MySQL works, so please bear that in mind. ![]()
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