sql - many to many relationship mysql design -


Many users can have multiple tabs, so I designed this table 

  UID (PK) User-Tab UID (FK) TabID (FK) Tab Tab IID (PK)   
 But when I  FK  to the  User-tab  I got this error  
  1050 - table '. \ Db \ tab @ 002duser 'already exists    
 
 
 This is your DB-design or There is no problem with existing records, but there is a naming problem.  
 MySQL rules for naming unquoted identifiers are: use  CamelCase  or  dash-style-writing ,  
  snake_case_writing    
:  
 
 allowed characters (wire, not value) in uncovered identifiers:  
 ASCII: [0- 9, as, as $ _] (original Latin letter, digits 0-9, dollar, underscore)  
 extended: U + 0080. U + FFFF  < / Blockquote> 
  Edit   
 Another abridgment from Docs ( Ore for reading this and me )  
 
 Naming Convention For identifiers formed by several words, separate each component with underscores rather than capitalization. Thus, use my_var instead of myvar or MyVar.  
 Avoid capital letters except class names; Class names should begin with a capital letter.  
 class items; Category Query_arena; Class log_event; Avoid function names, structure elements, or variables that start or end with '_'.  
 Use long function and variable name in English This will make your code easier to read for all developers.

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