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doc/sql.extensions/README.user_management

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+SQL Language Extension: CREATE/ALTER/DROP USER
+
+   Implements capability to manage users from regular database attachment.
+
+Author:
+   Alex Peshkoff <peshkoff@mail.ru>
+
+Syntax is:
+
+   CREATE USER name {PASSWORD 'password'} [FIRSTNAME 'firstname'] [MIDDLENAME 'middlename'] [LASTNAME 'lastname'];
+   ALTER USER name [PASSWORD 'password'] [FIRSTNAME 'firstname'] [MIDDLENAME 'middlename'] [LASTNAME 'lastname'];
+   DROP USER name;
+
+Description:
+
+Makes it possible to add, modify and delete users in security database using SQL language. 
+
+Firebird 2.5 has no setup to make it possible to setup different security databases. But since 3.0 
+this is supposed to become standard feature, therefore it's highly recommended (though currently the 
+result does not change) to modify users being connected to really that database, where modification 
+is required. 
+
+CREATE and DROP clauses are available only for SYSDBA (or other user, granted RDB$ADMIN role in 
+security database). Ordinary user can ALTER his own password and/or wide names. Attempt to modify
+another user will fail.
+
+At least one of PASSWORD, FIRSTNAME, MIDDLENAME or LASTNAME must be present in ALTER USER statement.
+Also notice that PASSWORD clause is required when creating new user.
+
+Sample:
+
+   CREATE USER alex PASSWORD 'test';
+   ALTER USER alex FIRSTNAME 'Alex' LASTNAME 'Peshkoff';
+   ALTER USER alex PASSWORD 'IdQfA';
+   DROP USER alex;