There are 4 tables table1,table2开发者_StackOverflow中文版,table3
and table4
table1 has got 60000 datas
table2 has got 85000 datas
table3 has got 78000 datas
table4 has got 68000 datas
indexes on all tables are same but one got less than or more than each other. for example name john
is stored in all 4 tables.but mathew
is stored in may be two tables but not in other two and ethan
may be stored in 3 tables but not may be in 4th one.
upto say first 60k all index/names are same but after that it is irregular
so how can I merge all these table into 1 table?? all four tables got 2 columns each and first one is name and second is its details
There are probably more efficient ways of doing this, but this was the first thing that came to mind.
INSERT INTO table5
SELECT DISTINCT Table5Content.* FROM (
SELECT * FROM table1
UNION ALL
SELECT * FROM table2
UNION ALL
SELECT * FROM table3
UNION ALL
SELECT * FROM table4
UNION ALL
SELECT * FROM table5
) as Table5Content
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