1 python reports an error when running mysql statement
As we all know, python has a translation mechanism. %s and %d will be translated into strings or numbers, and fuzzy queries of sql also need to be used. By %, when all fuzzy queries are performed, it would be very embarrassing if the query condition happens to be a variable.
The solution is actually very simple, just take out the strings that need to be fuzzy queried from the sql and splice them together
Wrong way
<code>shopId = "zbw_010002"</code><code><br></code><code>'''select * from base_saleflows where shopId='{0}' and card_id is not NULL and standard_cls4 like "%湿巾%" '''.format(shopId)</code>
Found that it was wrong, mysql cannot run such a statement.
<code>args='%湿巾%'</code><code>shopId = "zbw_010002"</code><code>mysql_sentence='''select a.shopId, a.sale_money,a.card_id ,a.standard_cls4 from base_saleflows a join base_vips b on a.card_id = b.card_id where a.shopId='{0}' and a.card_id is not NULL and a.standard_cls4 like '{1}' '''.format(shopId,args)</code><code>print(mysql_sentence)</code><code><br></code>
The result is
select * from base_saleflows a join base_vips b on a.card_id = b.card_id where a.shopId='zbw_010002' and a.card_id is not NULL and a.standard_cls4 like '%湿巾%'
2 String grouping and splicing
Group the cls3 column according to the serial number flow_no and splice strings. The splicing symbol is '-'
# 分组拼接result = vipsaleflow_common.pivot_table(values='standard_cls3',index='flow_no',aggfunc=lambda x:x.str.cat(sep='-'))
quarter# according to ( year , quarter , branch number , wet wipes type) ##Number of new customers
四 Derived based on timestamp year, month and quarter
saleflow['oper_date']=saleflow['oper_date'].astype(str) #字符串saleflow['oper_date'] = saleflow.oper_date.apply(lambda x:datetime.strptime(x, '%Y-%m-%d %H:%M:%S'))saleflow["month"] = saleflow.oper_date.map(lambda x: x.month)saleflow["year"] = saleflow.oper_date.map(lambda x: x.year)#https://www.it1352.com/584941.htmllookup = {1: 1, 2: 1,3: 1,4: 2, 5: 2, 6: 2, 7: 3,8: 3,9: 3,10: 4, 11: 4,12: 4}saleflow['Season'] = saleflow['oper_date'].apply(lambda x: lookup[x.month]) saleflow['YearMonth'] = saleflow['oper_date'].map(lambda x: 100*x.year + x.month)
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