有没有办法用python sqlite3迭代地将列输入到数据库中？

Question

def db_include(path, filename):
    full_file_path = path + filename
    patterns = pattern_retrieval(full_file_path)
    db_file = 'sequencesdb.db'
    conn = sqlite3.connect(db_file)
    try:
        c = conn.cursor()
        columns = list()
        columns_data = list()
        #create table
        for key, value in patterns.items():
            columns.append(key)
            columns_data.append(value)
        #create column names
        c.execute('''CREATE TABLE IF NOT EXISTS sequences ()''')

The pattern_retrieval function returns a dictionary

The dictionary is stored in patterns variable

now I want to create a table called sequences in sequences.db but I want each column to have the name of a key in the patterns variable.This is to help me then insert ints into each column after creating the db.

PATTERNS_DB SCHEMA

sequences table

|pattern1|pattern2|pattern3|

|42 | 67 | 78

But I want to do all this programatically.

Answer 1

• After trial and error, I think the best thing to do is to first run

c.execute('''CREATE TABLE IF NOT EXISTS sequences(EMPTY TEXT)''')

• to create a the table with a default column which can be deleted later then run

for i in range(len(columns)):
    addColum = f"ALTER TABLE sequences ADD COLUMN {columns[i] INTEGER}"
    c.execute(addColumn)
    conn.commit()

Answer 2

You can build the CREATE TABLE statement like this:

s = "CREATE TABLE sequences (" + ', '.join(f"{col} INTEGER" for col in columns) + ")"
c.execute(s)

Or, more secure:

s = "CREATE TABLE sequences (" + ', '.join(["? INTEGER"]*len(columns)) + ")"
c.execute(s, columns)

Or you could use ALTER TABLE:

# columns needs to be a list of tuples for this to work:
c.executemany("ALTER TABLE sequences ADD COLUMN ? INTEGER", columns)