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- PERMIT(QUEL) 2/7/79 PERMIT(QUEL)
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- NAME
- permit - add permissions to a relation
-
- SYNOPSIS
- _d_e_f_i_n_e _p_e_r_m_i_t oplist { _o_n | _o_f | _t_o } var [ (attlist) ]
- _t_o name [ _a_t term ] [ _f_r_o_m time _t_o time ]
- [ _o_n day _t_o day ] [ _w_h_e_r_e qual ]
-
- DESCRIPTION
- The _p_e_r_m_i_t statement extends the current permissions on the
- relation specified by _v_a_r. _O_p_l_i_s_t is a comma separated list
- of possible operations, which can be _r_e_t_r_i_e_v_e, _r_e_p_l_a_c_e,
- _d_e_l_e_t_e, _a_p_p_e_n_d, or _a_l_l; _a_l_l is a special case meaning all
- permissions. _N_a_m_e is the login name of a user or the word
- _a_l_l. _T_e_r_m is a terminal name of the form `tty_x' or the key-
- word _a_l_l; omitting this phrase is equivalent to specifying
- _a_l_l. _T_i_m_es are of the form `hh:mm' on a twenty-four hour
- clock which limit the times of the day during which this
- permission applies. _D_a_ys are three-character abbreviations
- for days of the week. The _q_u_a_l is appended to the qualifi-
- cation of the query when it is run.
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- Separate parts of a single _p_e_r_m_i_t statement are conjoined
- (ANDed). Different _p_e_r_m_i_t statements are disjoined (ORed).
- For example, if you include
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- . . . to eric at tty4 . . .
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- the _p_e_r_m_i_t applies only to eric when logged in on tty4, but
- if you include two _p_e_r_m_i_t statements
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- . . . to eric at all . . .
- . . . to all at tty4 . . .
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- then when eric logs in on tty4 he will get the union of the
- permissions specified by the two statements. If eric logs
- in on ttyd he will get only the permissions specified in the
- first _p_e_r_m_i_t statement, and if bob logs in on tty4 he will
- get only the permissions specified in the second _p_e_r_m_i_t
- statment.
-
- The _p_e_r_m_i_t statement may only be issued by the owner of the
- relation. Although a user other than the DBA may issue a
- _p_e_r_m_i_t statement, it is useless because noone else can ac-
- cess her relations anyway.
-
- _P_e_r_m_i_t statements do not apply to the owner of a relation or
- to views.
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- The statements
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- define permit all on x to all
- define permit retrieve of x to all
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- with no further qualification are handled as special cases
- and are thus particularly efficient.
-
- EXAMPLES
- range of e is employee
- define permit retrieve of e (name, sal) to marc
- at ttyd from 8:00 to 17:00
- on Mon to Fri
- where e.mgr = "marc"
-
- range of p is parts
- define permit retrieve of e to all
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- SEE ALSO
- destroy(quel)
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-