When using SQL databases, we might need a database like to add many records, then we can use the SQL statement to be implemented, the statement is as follows:
- add a record
INSERT INTO tableName (col1, col2, col3) VALUES (1,2,3)
- Add multiple records
INSERT INTO tableName (col1, col2, col3)
the SELECT 3,4,5
UNION ALL
the SELECT 6,7,8
- a further read from a plurality of data added to the table to a new table in
the INSERT the INTO tableName (col1, col2, col3)
the SELECT A, B, C on tableA the FROM
- read from the other plurality of tables to add data to the new table,
the INSERT the INTO tableName (col1, col2, col3)
the SELECT A, B, C the FROM on tableA the WHERE A =. 1
the UNION ALL
the SELECT A, B, C the FROM on tableB the WHERE A = 2
the upper side into the code can be omitted!
Union all upper code if changed Union, the same recording only once inserted, the insertion will not be repeated.
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