带模式名查询，用引号

import psycopg2


# 创建连接对象
# 连接 -> 数据库名 -> 模式名 -> 表名
conn = psycopg2.connect(database="db_name", user="postgresql", password="postgresql", host="IP", port="xxxx")

# 创建指针对象
cur = conn.cursor()


# 获取结果
# 'SELECT * FROM "schema_name"."table_name" limit 10'  # schema_name和table_name一定要用双引号包起来，单引号会出错
# 例如：
# cur.execute("SELECT * FROM '{}'.'{}' limit 10".format(schema_name, table_name))
# psycopg2.errors.SyntaxError: syntax error at or near "'schema_name'"
# LINE 1: SELECT * FROM 'schema_name'.'table_name...

# cur.execute('SELECT * FROM "schema_name"."table_name" limit 10')    # 数据表太大可以用limit限制一下

schema_name = "schema_name"
table_name = "table_name"
# print('SELECT * FROM "{}"."{}" limit 10'.format(schema_name, table_name))
cur.execute('SELECT * FROM "{}"."{}" limit 10'.format(schema_name, table_name))
results = cur.fetchone()  # 取一条数据
# results = cur.fetchall()
print(results)

# 关闭连接
conn.commit()
cur.close()
conn.close()

https://blog.csdn.net/u012325865/article/details/82563744