MYSQL WORKBENCH BOOLEAN WINDOWS 7
Developer Notes - MySQL Workbench CE for Windows version 5.2.41 revision 9727 Configuration Directory: C:\Users\jeff\AppData\Roaming\MySQL\Workbench Data Directory: C:\Program Files (x86)\MySQL\MySQL Workbench 5.2 CE Cairo Version: 1.8.8 OS: Microsoft Windows 7 Home Premium Edition (build. CREATE TABLE quantum ( id bigint (20) NOT NULL AUTOINCREMENT, type enum ('a','b','c','d','e') CHARACTER SET latin1 NOT NULL, PRIMARY KEY (id) ) ENGINEMyISAM AUTOINCREMENT11173 DEFAULT CHARSETutf8. I'm using MySQL Workbench 6.3 for my database. Also, make sure that you place a comment in the MySQL comment field for your bit_flags field. Description: When I export my Data model to SQL, the boolean data type is changed to tinyint. As the title suggests, i'm trying to add more elements to my existing ENUM-type column.
Make sure you have MySQL do your masking and shifting - this will be significantly faster than having the web-scripting language (PHP, ASP, etc.) do it. We will declare the data type of the healthChecked column as BOOLEAN and runCompleted as BOOL and. Don’t just shift, or you will create hell for yourself and others in the future. Let us create one table named marathonplayers that will store the participants’ details in the marathon and have columns that will store boolean values in it, such as healthChecked and runCompleted. Some future programmer will invariably use the next seven bits, so you must mask. Since you have 8 bits, you have potentially 8 boolean variables from one byte. You can run statements like these as you test SELECT (128 & 128) > 7 SELECT (t.bit_flags & 128) > 7 AS myBool FROM myTable t
Now the entire number (which, in this case, is 1) is your value. Mask (hide) the seven rightmost bits (using the bitwise operator &), and shift the 8th bit seven spaces to the right, ending up with 00000001. Until MySQL implements a bit datatype, if your processing is truly pressed for space and/or time, such as with high volume transactions, create a TINYINT field called bit_flags for all your boolean variables, and mask and shift the boolean bit you desire in your SQL query.įor instance, if your left-most bit represents your bool field, and the 7 rightmost bits represent nothing, then your bit_flags field will equal 128 (binary 10000000).
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