Method 1: Using raw SQL queries The first method involves executing a raw SQL query to check if the table exists. Here is the code to do that Example import sqlite3 # create a connection to the database conn = sqlite3.connect('example.db') # create a cursor object to execute queries...
def check_table_exists(self, database_name, table_name): """Checks whether the Hive table exists. Args: database_name (str): Hive database name. table_name (str): Hive table name. Returns: boolean : True, if table exists else False. """ results = self.execute_query( "SHOW TABLES...
Check if Table Exists You can check if a table exist by listing all tables in your database with the "SHOW TABLES" statement: Example Return a list of your system's databases: importmysql.connector mydb = mysql.connector.connect(
callback( [Output('table-name', 'invalid'), Output('table-name', 'valid')], Input('table-name', 'value') ) def check_table_name(value): ''' 检查表名是否合法 ''' if value: # 查询库中已存在非系统表名 exists_table_names = ( pd .read_sql('''SELECT tablename FROM pg_tables'...
SQL_CREATE_TABLE = '''CREATE TABLE IF NOT EXISTS PEOPLE (ID INT PRIMARY KEY NOT NULL, NAME TEXT NOT NULL, AGE INT NOT NULL);''' def create_db_table(self): """ 初始化表 :return: """ self.conn.execute(SQL_CREATE_TABLE) 接下来,我们通过增删改查来操作数据表 1、新增 同样以新增单条...
cursor() sql_check = '''drop table if exists movies_data15;''' # 判断movies_data表是否存在,存在则drop sql_create = '''create table movies_data15(date varchar(8), avgSeatView varchar(8), avgShowView varchar(8), boxInfo varchar(10), boxRate varchar(8), movieId varchar(10), movie...
运行以下 T-SQL 语句以创建存储过程PredictTipRxPy。 此存储过程使用与先前存储过程相同的输入并创建相同的评分类型,但使用具有 SQL Server 机器学习的 revoscalepy 包中的函数。 SQL复制 DROPPROCEDUREIFEXISTSPredictTipRxPy; GOCREATEPROCEDURE[dbo].[PredictTipRxPy] (@modelvarchar(50), @inquerynvarchar(max...
output_file = args.OUTPUT_FILEifargs.hash: ha = args.hash_algorithmprint("File hashing enabled with {} algorithm".format(ha))ifnotargs.log:print("Log file not defined. Will write to stdout") 当组合成一个脚本并在命令行中使用-h参数执行时,上述代码将提供以下输出: ...
2.3 Python与SQL集成 import sqlite3 import pandas as pd # 创建内存数据库 conn = sqlite3.connect(':memory:') df.to_sql('employees', conn, if_exists='replace', index=False) # 执行SQL查询 query = """ SELECT department, AVG(salary) as avg_salary ...
#创建表SQL_CREATE_TABLE = '''CREATE TABLE IF NOT EXISTS PEOPLE (ID INT PRIMARY KEY NOT NULL, NAME TEXT NOT NULL, AGE INT NOT NULL);''' def create_db_table(self): """ 初始化表 :return: """ self.conn.execute(SQL_CREATE_TABLE) ...