![]() That will lead to potentially less disk reads and less writes. The take-away we can draw from all of this is that one should use a VARCHAR field instead of TEXT for columns between 255 and 65k characters if possible. ![]() TIP: Since TEXT fields can get quite long, Navicat has a FORM view that give them more room: Conclusion As you can see, it contains the text, mediumtext, and longtext types:Īs for the VARCHAR type, you can also select it from the Type drop-down, but then you should edit the Length value if you want a value other than 255 (the default). Under the Type header, you can select a column's data type simply by selecting it from a drop-down. In both Navicat for MySQL and Navicat Premium, the Object Designer allows you to create and maintain all sorts of database objects, including Tables, Views, Functions, Indexes, and, of course, columns. Selecting VARCHAR and TEXT Types in Navicat MEDIUMTEXT stores strings up to 16 MB, and LONGTEXT up to 4 GB! It should go without saying that you should avoid using these larger types unless you have a lot of storage space. The latter two are for storing textual content that is longer than 65,535 characters. Should you require the TEXT type, know that there are actually three flavors in addition to TEXT, there are also MEDIUMTEXT or LONGTEXT varieties. Using a TEXT column in a sort will require the use of a disk-based temporary table, as the MEMORY (HEAP) storage engine.Meanwhile, TEXT is stored off table with the table having a pointer to the location of the actual storage. To get the number of characters in a string in MySQL and PostgreSQL, you use the CHARLENGTH function instead. Of course, how much faster depends on both your data and your hardware. The LENGTH function returns the number of bytes in some relational database systems such as MySQL and PostgreSQL. VARCHAR is stored inline with the table (at least for the MyISAM storage engine), making it potentially faster when the size is reasonable.A VARCHAR can be part of an index whereas a TEXT field requires you to specify a prefix length, which can be part of an index.TEXT fields have a fixed max size of 65,535 characters. ![]()
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