Question

我按seconditemid对数据进行分组。是否可以计算每行sum(extcost)在总和中的百分比（所有表格数据的总结合）？

例如我们在结果集中有2行，A1总计4500，A2总计5500，总计应为10000，A1占45％，A2占55％。

seconditemid|ratio
--------------------
A1          |.45
--------------------
A2          |.55

我的查询是

select seconditemid,  
    round(100.0*(
        sum(case when seconditemid = ---the current row's seconditemid
        then 1 else 0 end)/sum(extcost)
    ),1) as ratio
from inventory_fact f inner join item_master_dim i using (itemmasterkey)
where transtypekey = 1
group by seconditemid
order by 2 desc;

这不起作用。我尝试先创建一个视图

create view v1 as(
    select sum(extcost) as sumExtcost from inventory_fact
);

并从中选择

select seconditemid, round(100.0*(
        sum(extcost)/sum(v1.sumextcost)
    ),1) as ratio
from from inventory_fact f inner join item_master_dim i using (itemmasterkey), v1
where transtypekey = 1
group by seconditemid
order by 2 desc;

然后每列的比例变为0。

Answer 1

我们来看看这个样本架构：

<!DOCTYPE html>
<html>
<head>
<title> </title>
</head>
<body>
<script>
var alphabet = ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z",]
var input = prompt("Enter In The Text That You Want To Decode")
var results = []

//Decoding
var ceaser_alphabet = []

var cAlphabet_creation_progress = 1

var ceaser_progress = 1
var decoding_progress = 1

var decoded_message = ""

var slice1 = []
var slice2 = []

var decoder = function () {
//Uses 25 instead of 26 because the first item in an array is counted as "0"
    slice1 = alphabet.slice(0, (26 - ceaser_progress))
    slice2 = alphabet.slice((26 - ceaser_progress), 26)

    while (cAlphabet_creation_progress < 26) {
        if (cAlphabet_creation_progress < slice1.length) {
            ceaser_alphabet.push(slice1[cAlphabet_creation_progress])
        } else {
            ceaser_alphabet.push(slice2[cAlphabet_creation_progress])
        }
    }

//Decoding
    while(decoding_progress < input.length) {
        if (!input.charAt(decoding_progress) == " ") {
            decoded_message = decoded_message + ceaser_alphabet[ceaser_alphabet.indexOf(alphabet.indexOf(input.charAt(decoding_progress)))]
            decoding_progress++
        } else {
            decoded_message = decoded_message + " "
        }
    }

    if (decoding_progress == input.length) {
        results.push(decoded_message)
        ceaser_progress++
        decoding_progress = 1
        ceaser_alphabet = []
        decoded_message = ""
    }
}
var possibilities_left = 26
while (possibilities_left > 0) {
    possibilities_left-- 
    decoder()
}
console.log(results)

</script>
</body>
</html>

以下是查询：

CREATE TABLE c (
    seconditemid text,
    total int
);

INSERT INTO c (seconditemid, total) VALUES ('A1', 4500);
INSERT INTO c (seconditemid, total) VALUES ('A2', 5500);

- ＆GT;

SELECT seconditemid, total, 
       total::float / (SUM(total) OVER()) as ratio
FROM c;

Answer 2

您的第二个查询应该没问题但是0已经float了。您需要明确地将总和值转换为SELECT g.seconditemid, g.extcost::float / t.total::float percent -- << here FROM ( SELECT seconditemid, SUM(extcost) extcost FROM inventory_fact GROUP BY seconditemid ) g CROSS JOIN ( SELECT SUM(extcost) total FROM inventory_fact ) t ORDER BY percent DESC。

以下是没有视图的示例

V/SDL     (29083): SDL audio: opening device
V/SDL     (29083): SDL audio: wanted stereo 16-bit 44.1kHz, 4096 frames buffer
I/AudioPolicyManager( 2267): getOutputForAttr() device 0x2, samplingRate 44100, format afcad8d8, channelMask 1, flags 0
I/AudioPolicyManager( 2267): getOutputForAttr() output 2
W/AudioPolicyIntefaceImpl( 2267): Skipped to add effects on session 182
I/AudioPolicyManager( 2267): startOutput() output 2, stream 3, session 182
I/AudioPolicyManager( 2267): changeRefCount() stream 3, count 1
I/AudioPolicyManager( 2267): setOutputDevice() setting same device 0002 or null device for output 2
V/SDL     (29083): SDL audio: got stereo 16-bit 44.1kHz, 4096 frames buffer
I/python  (29083): [WARNING] [AudioSDL2   ] Unable to load sounds/applause.wav: Mix_LoadWAV_RW with NULL src
D/AudioMixer( 2267): setResampler format 1, data ch 2, src 44100, dst 48000, dnmix 0, reformat 0
D/SoundAliveResampler( 2267): [SoundAliveResampler] Init+++
I/AudioHardwareTinyALSA( 2267): AudioStreamOutALSA::write setDevice
D/AudioHardwareTinyALSA( 2267): OutALSA::setDevice: mode = 0, newDevice=0x2, currentDevice=0x2 ,force= 0
D/AudioHardwareTinyALSA( 2267): OutALSA::setDevice: mDevice 0x2, newDevice = 0x2
D/AudioHardwareTinyALSA( 2267): setOutputVolume
D/TinyUCM ( 2267): setModifier Normal, en=1
I/AudioHardwareTinyALSA( 2267): OutALSA::setDevice: mHandle NULL mode[0], Device[00000002] nDevice:3 
I/AudioHardwareTinyALSA( 2267): Open:+ mDefaults->direction=0 device=3
D/AudioHardwareTinyALSA( 2267): Channel: 2, Samplerate: 48000, Format: 0, Period Size: 960, Period Count: 4

输出：

| seconditemid | percent |
|--------------|---------|
|           A2 |    0.55 |
|           A1 |    0.45 |

integer division truncates the results

PostgreSQL计算当前行值与总数之和的百分比

2 个答案: