如前所述，臨時(shí)表將只要會(huì)話持續(xù)就活著。如果在一個(gè)PHP腳本運(yùn)行的代碼，當(dāng)腳本執(zhí)行完畢后，臨時(shí)表將被自動(dòng)銷毀。如果您是通過MySQL客戶端程序連接到MySQL數(shù)據(jù)庫服務(wù)器，那么臨時(shí)表會(huì)一直存在，直到您關(guān)閉客戶端或者手動(dòng)銷毀表。

例子：

下面是一個(gè)例子，顯示臨時(shí)表的用法：

mysql> CREATE TEMPORARY TABLE SALESSUMMARY (
    -> product_name VARCHAR(50) NOT NULL
    -> , total_sales DECIMAL(12,2) NOT NULL DEFAULT 0.00
    -> , avg_unit_price DECIMAL(7,2) NOT NULL DEFAULT 0.00
    -> , total_units_sold INT UNSIGNED NOT NULL DEFAULT 0
);
Query OK, 0 rows affected (0.00 sec)

mysql> INSERT INTO SALESSUMMARY
    -> (product_name, total_sales, avg_unit_price, total_units_sold)
    -> VALUES
    -> ('cucumber', 100.25, 90, 2);

mysql> SELECT * FROM SALESSUMMARY;
+--------------+-------------+----------------+------------------+
| product_name | total_sales | avg_unit_price | total_units_sold |
+--------------+-------------+----------------+------------------+
| cucumber     |      100.25 |          90.00 |                2 |
+--------------+-------------+----------------+------------------+
1 row in set (0.00 sec)

當(dāng)你發(fā)出一個(gè)SHOW TABLES命令，臨時(shí)表不會(huì)被列在列表中?，F(xiàn)在，如果注銷MySQL的會(huì)話，然后發(fā)出SELECT命令，這時(shí)你會(huì)發(fā)現(xiàn)在數(shù)據(jù)庫中沒有可用的數(shù)據(jù)。臨時(shí)表也就不存在了。

刪除臨時(shí)表：

默認(rèn)情況下，當(dāng)你的數(shù)據(jù)庫連接被終止，所有的臨時(shí)表被MySQL刪除。您如果還是想要?jiǎng)h除的他們，那么可發(fā)出DROP TABLE命令。

下面是刪除一個(gè)臨時(shí)表的例子。

mysql> CREATE TEMPORARY TABLE SALESSUMMARY (
    -> product_name VARCHAR(50) NOT NULL
    -> , total_sales DECIMAL(12,2) NOT NULL DEFAULT 0.00
    -> , avg_unit_price DECIMAL(7,2) NOT NULL DEFAULT 0.00
    -> , total_units_sold INT UNSIGNED NOT NULL DEFAULT 0
);
Query OK, 0 rows affected (0.00 sec)

mysql> INSERT INTO SALESSUMMARY
    -> (product_name, total_sales, avg_unit_price, total_units_sold)
    -> VALUES
    -> ('cucumber', 100.25, 90, 2);

mysql> SELECT * FROM SALESSUMMARY;
+--------------+-------------+----------------+------------------+
| product_name | total_sales | avg_unit_price | total_units_sold |
+--------------+-------------+----------------+------------------+
| cucumber     |      100.25 |          90.00 |                2 |
+--------------+-------------+----------------+------------------+
1 row in set (0.00 sec)
mysql> DROP TABLE SALESSUMMARY;
mysql>  SELECT * FROM SALESSUMMARY;
ERROR 1146: Table 'TUTORIALS.SALESSUMMARY' doesn't exist

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SQL臨時(shí)表

例子：

刪除臨時(shí)表：