32v 1m join
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JOIN(1) UNIX Programmer's Manual JOIN(1)
join - relational database operator
join [ options ] file1 file2
_J_o_i_n forms, on the standard output, a join of the two rela- tions specified by the lines of _f_i_l_e_1 and _f_i_l_e_2. If _f_i_l_e_1 is `-', the standard input is used.
_F_i_l_e_1 and _f_i_l_e_2 must be sorted in increasing ASCII collating sequence on the fields on which they are to be joined, nor- mally the first in each line.
There is one line in the output for each pair of lines in _f_i_l_e_1 and _f_i_l_e_2 that have identical join fields. The output line normally consists of the common field, then the rest of the line from _f_i_l_e_1, then the rest of the line from _f_i_l_e_2.
Fields are normally separated by blank, tab or newline. In this case, multiple separators count as one, and leading separators are discarded.
These options are recognized:
-a_n In addition to the normal output, produce a line for each unpairable line in file _n, where _n is 1 or 2.
-e _s Replace empty output fields by string _s.
-j_n _m Join on the _mth field of file _n. If _n is missing, use the _mth field in each file.
-o _l_i_s_t Each output line comprises the fields specifed in _l_i_s_t, each element of which has the form _n._m, where _n is a file number and _m is a field number.
-t_c Use character _c as a separator (tab character). Every appearance of _c in a line is significant.
With default field separation, the collating sequence is that of _s_o_r_t -_b; with -t, the sequence is that of a plain sort.
The conventions of _j_o_i_n, _s_o_r_t, _c_o_m_m, _u_n_i_q, _l_o_o_k and _a_w_k(1) are wildly incongruous.