Question

我正在尝试返回一个查询，当返回与课程代码相关的所有课程时，例如'CSC'会给我一个[（'CSCA08H3F'），（'CSCA20H3F'），（'CSCA67H3F）的元组'，）]...等等。我知道我必须使用LIKE子句，但我似乎做错了，感觉就像有一种更简单的方法来做这个大声笑......

def create_course_table(db, course_file):
'''Courses Table should be ID,Course,Section,Name'''

con = sqlite3.connect(db)
cur = con. cursor()

cur.execute('''DROP TABLE IF EXISTS Courses''')

# create the table
cur.execute('''CREATE TABLE Courses( ID TEXT , Course TEXT , 
Sections TEXT , Name TEXT)''')

# Read CSV File
csv_reader = open(course_file, 'r')
csv_reader.readline()      

# Insert the rows

for line in csv_reader:
    course = line.strip().split(',')
    ID = course[0]
    Course = course[1]
    Section = course[2]
    Name = course[3:]
    for names in Name:
        cur.execute('''INSERT INTO Courses VALUES (?, ?, ?, ?)''', 
                    (ID, Course, Section, names))    

# commit and close the cursor and connection
con.commit()
cur.close()
con.close()

db = 'exams.db'


def find_dept_courses(db, dept):
'''Return the courses from the given department.  Use  the "LIKE" 
clause in your SQL query for the course name.'''

return run_query(db, ''' SELECT Course FROM Courses WHERE  LIKE Course 'ACT%' 
OR LIKE Course 'AFS%' OR LIKE Course 'ANT%' OR LIKE Course 'AST%' 
OR LIKE Course 'BIO%' 
OR LIKE Course 'CHM%' OR LIKE Course CIT%' OR LIKE Course 'CLA%' 
OR LIKE Course 'CRT%' OR LIKE Course 'CSC%' OR LIKE Course 'CTL%' 
OR LIKE Course 'ECT%' OR LIKE Course 'EES%' OR LIKE Course 'ENG%' 
OR LIKE Course 'EST%' OR LIKE Course 'FRE%' OR LIKE Course 'FST%' 
OR LIKE Course 'GAS%'
OR LIKE Course 'GGR%' OR LIKE Course 'HIS%' OR LIKE Course 'HLT%'
OR LIKE Course 'IDS%' OR LIKE Course 'JOU%' OR LIKE Course 'LGG%'
OR LIKE Course 'LIN%' OR LIKE Course 'MAT%' OR LIKE Course 'MDS%'
OR LIKE Course 'MGA%' OR LIKE Course'MGE%' OR LIKE Course 'MGF%'
OR LIKE Course 'MGH%' OR LIKE Course 'MGI%' OR LIKE Course 'MGM%'
OR LIKE Course 'MGO%' OR LIKE Course 'MGS%' OR LIKE Course 'MGT%'
OR LIKE Course 'NRO%' OR LIKE Course 'PHL%' OR LIKE Course 'PHY%'
OR LIKE Course 'PLI%' OR LIKE Course 'POL%' OR LIKE Course 'PPG%'
OR LIKE Course 'PSC%' OR LIKE Course 'PSY%' OR LIKE Course 'RLG%'
OR LIKE Course 'SOC%' OR LIKE Course 'STA%' OR LIKE Course 'VPA%'
OR LIKE Course 'VPD%' OR LIKE Course 'VPM%' OR LIKE Course 'WST%' AND WHERE Course = ? ''', [dept])

任何帮助或意见将不胜感激。

Answer 1

熟悉正确的syntax of the LIKE clause.

您已将列名称放在＆＃34; LIKE＆＃34;之后。列名出现在＆＃34; LIKE＆＃34;。

之前

以下查询将从课程列以指定字符串开头的课程中的所有行返回“课程”列。

SELECT Course FROM Courses WHERE Course LIKE ? || "%";

代替？带有所需的前缀。

Answer 2

由于所有Course列项都是大写的，因此您可以使用IN而不是LIKE。

在提示符下进行简单测试，该提示显示课程中使用的printf可以将其修剪为3个字符，因此您可以比较每个项目的3个字符进行搜索。

sqlite> .schema
CREATE TABLE test (one text);
sqlite> select * from test;
abcd
efgh
ijkl
abcd
efgh
ijkl
abcd
efgh
ijkl
sqlite> select one from test where printf('%.3s',one) in ('abc');
abcd
abcd
abcd
sqlite>

因此find_dept_courses（）可以使用：

def find_dept_courses(db, dept):
    '''Return the courses from the given department.  Use the "IN"
    clause in your SQL query for the course name.'''

    return run_query(db, ''' SELECT Course FROM Courses WHERE printf('%.3',Course)
    IN ('ACT','AFS','ANT','AST','BIO','CHM','CIT','CLA','CRT','CSC','CTL',
    'ECT','EES','ENG','EST','FRE','FST','GAS','GGR','HIS','HLT','IDS','JOU',
    'LGG','LIN','MAT','MDS','MGA','MGE','MGF','MGH','MGI','MGM','MGO','MGS',
    'MGT','NRO','PHL','PHY','PLI','POL','PPG','PSC','PSY','RLG','SOC','STA',
    'VPA','VPD','VPM','WST') AND WHERE Course = ? ''', [dept])

编辑：如果需要sqlite有一个upper（）和lower（）函数来强制大小写。 sqlite upper function

同一列中的多个LIKE条件

2 个答案: