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occurs as described in Section 5.6.6.3, “Using Version Tokens” , which provides details about the syntax for specifying tokens, as well as additional examples. 

• version_tokens_delete( name_list ) 

Deletes tokens from the server’s list of version tokens using the name_list  argument and returns a binary string that indicates the outcome of the operation. name_list  is a semicolon-separated list of version token names to delete. 

mysql> SELECT version_tokens_delete(’tok1;tok3’); 

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An argument of NULL  is treated as an empty string, which has no effect on the token list. 

version_tokens_delete()  deletes the tokens named in its argument, if they exist. (It is not an error to delete nonexisting tokens.) To clear the token list entirely without knowing which tokens are in the list, pass NULL  or a string containing no tokens to version_tokens_set() : 

mysql> SELECT version_tokens_set(NULL); 

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mysql> SELECT version_tokens_set(’’); 

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• version_tokens_edit( token_list ) 

Modifies the server’s list of version tokens using the token_list  argument and returns a binary string that indicates the outcome of the operation. token_list  is a semicolon-separated list of name = value pairs specifying the name of each token to be defined and its value. If a token exists, its value is updated with the given value. If a token does not exist, it is created with the given value. If the argument is NULL or a string containing no tokens, the token list remains unchanged. 

mysql> SELECT version_tokens_set(’tok1=value1;tok2=value2’); 

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mysql> SELECT version_tokens_edit(’tok2=new_value2;tok3=new_value3’); 

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• version_tokens_set( token_list ) 

Replaces the server’s list of version tokens with the tokens defined in the token_list  argument and returns a binary string that indicates the outcome of the operation. token_list  is a semicolon- separated list of name = value  pairs specifying the name of each token to be defined and its value. If the argument is NULL  or a string containing no tokens, the token list is cleared. 

