MySQL 5.6

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CREATE TABLE table1(col1 VARCHAR(2),A INT,B INT,C INT)
INSERT INTO table1 VALUES('N1',1,0,1),
                         ('N2',0,1,0),
                         ('N3',1,0,0)
CREATE TABLE table2 AS
SELECT CONCAT(col1,' ',
                   CASE WHEN A = 1 THEN 'A' ELSE '' END,
                   CASE WHEN B = 1 THEN 'B' ELSE '' END,
                   CASE WHEN C = 1 THEN 'C' ELSE '' END) as new_col
  FROM table1
SELECT * FROM table2


new_col


N1 AC

N2 B

N3 A


CREATE TABLE table3 AS
SELECT SUBSTRING(new_col,1,instr(new_col,' ')-1) AS col1,
       CASE WHEN instr(new_col,'A') > 0 THEN 1 ELSE 0 END AS A,
       CASE WHEN instr(new_col,'B') > 0 THEN 1 ELSE 0 END AS B,
       CASE WHEN instr(new_col,'C') > 0 THEN 1 ELSE 0 END AS C
  FROM table2
SELECT * FROM table3


col1
A
B
C


N1
1
0
1

N2
0
1
0

N3
1
0
0