我试图使用一个选择语句从某个MySQL表中获得除一个以外的所有列。有什么简单的方法吗?
编辑:在这个表格中有53列(不是我的设计)
当前回答
只做
SELECT * FROM table WHERE whatever
然后用您最喜欢的编程语言php删除该列
while (($data = mysql_fetch_array($result, MYSQL_ASSOC)) !== FALSE) {
unset($data["id"]);
foreach ($data as $k => $v) {
echo"$v,";
}
}
其他回答
也许我有一个解决Jan Koritak指出的矛盾的方法
SELECT CONCAT('SELECT ',
( SELECT GROUP_CONCAT(t.col)
FROM
(
SELECT CASE
WHEN COLUMN_NAME = 'eid' THEN NULL
ELSE COLUMN_NAME
END AS col
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'employee' AND TABLE_SCHEMA = 'test'
) t
WHERE t.col IS NOT NULL) ,
' FROM employee' );
表:
SELECT table_name,column_name
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'employee' AND TABLE_SCHEMA = 'test'
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
table_name column_name
employee eid
employee name_eid
employee sal
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
查询结果:
'SELECT name_eid,sal FROM employee'
(不要在大桌子上尝试，结果可能是……令人惊讶的!)
临时表
DROP TABLE IF EXISTS temp_tb;
CREATE TEMPORARY TABLE ENGINE=MEMORY temp_tb SELECT * FROM orig_tb;
ALTER TABLE temp_tb DROP col_a, DROP col_f,DROP col_z; #// MySQL
SELECT * FROM temp_tb;
DROP语法可能因数据库而异
据我所知，没有。你可以这样做:
SELECT col1, col2, col3, col4 FROM tbl
并手动选择所需的列。然而，如果你想要很多列，那么你可能只需要做一个:
SELECT * FROM tbl
忽略你不想要的。
针对你的特殊情况，我建议:
SELECT * FROM tbl
除非你只想要几列。如果你只想要四列，那么:
SELECT col3, col6, col45, col 52 FROM tbl
这很好，但如果您想要50个列，那么任何使查询变得(太?)难以阅读的代码。
即使要查询所有列，也最好指定要查询的列。
因此，我建议您在语句中写下每一列的名称(不包括您不想要的列)。
SELECT
col1
, col2
, col3
, col..
, col53
FROM table
虽然我同意Thomas的答案(+1;))，但我想补充一点，即我假设您不想要的列几乎不包含任何数据。如果它包含大量的文本、xml或二进制blob，那么请花时间单独选择每一列。否则你的表现就会受到影响。干杯!
