SELECT
CAST((CASE WHEN TRIM(DASM#)='' THEN '0' ELSE TRIM(DASM#) END) AS INTEGER) AS DASM,
DAIDAT,
DAINV# AS DAINV,
DALIN# AS DALIN,
CAST(TRIM(DAITEM) AS INTEGER) AS DAITEM,
TRIM(DABSW) AS DABSW,
TRIM(DAPCLS) AS DAPCLS,
DAQTY,
DAPRIC,
DAICOS,
DADPAL,
(DAPRIC-DAICOS+DADPAL)*DAQTY AS PROFIT
FROM
VIPDTAB.DAILYV
WHERE
CAST((CASE WHEN TRIM(DASM#)='' THEN '0' ELSE TRIM(DASM#) END) AS INTEGER)=30 AND
TRIM(DABSW)='B' AND
DAIDAT BETWEEN (YEAR(CURDATE())*10000) AND (((YEAR(CURDATE())+1)*10000)-1) AND
CAST(TRIM(DACOMP) AS INTEGER)=1
ORDER BY
CAST((CASE WHEN TRIM(DASM#)='' THEN '0' ELSE TRIM(DASM#) END) AS INTEGER),
DAIDAT,
DAINV#,
DALIN#
#!/bin/bash
perl -e '
while (<>) {
if (/^(.{15}) Program(\d+): The pool size: (\d+) \[High: (\d+) Norm: (\d+) Low: (\d+)\]$/) {
$timestamp = $1;
$program = $2;
$size = $3;
$high = $4;
$norm = $5;
$low = $6;
if (! defined $array{$timestamp}) {
# it takes care of duplicate timestamps
push(@timestamps, $timestamp);
}
$i = ($program - 1) * 4;
@{$array{$timestamp}}[$i .. $i + 3] = ($size, $high, $norm, $low);
}
}
foreach (@timestamps) {
print "$_,", join(",", map {$_ + 0} @{$array{$_}}[0 .. 15]), "\n";
}' logfile
会返回列表a=([1,2], [3,4], [5,6])
b=[[1,2], [3,4], [5,6]]
print(a[1])
print(a[1:2])
print(b[1])
print(b[1:2])
，但a[1]会返回元组[3,4]？a[2:3]与([3,4])相同。但是我错了。为什么list[1]（返回列表list[1:2]）的长度为2，但b[1]的长度会返回长度为1的列表[3,4]的列表？答案 0 :(得分：2)
在python中，语法array[x:y]将数组从索引x切片到y-1。因此，不是返回数组的值的array[x]，而是返回数组，只返回从x到y-1的元素