在MySQL中導出三張表，可以使用以下步驟：
CREATE TABLE tmp_table AS
SELECT * FROM table1
UNION ALL
SELECT * FROM table2
UNION ALL
SELECT * FROM table3;
SELECT * INTO OUTFILE '/path/to/output/file.csv'
FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"'
ESCAPED BY '\\'
LINES TERMINATED BY '\n'
FROM tmp_table;
/path/to/output/file.csv替換為你想要導出的CSV文件的路徑。導出的CSV文件將包含三張表的數據。請注意，導出數據時可能需要適當的權限。確保你有足夠的權限執行上述操作。
