Question

我创建了一个表，并且我被要求向名为no_semesters的列添加约束。条件是no必须是＆gt; = 0并且默认值不应为null，默认值为6.当我运行此语句时：

import numpy as np
import tensorflow as tf

# Insert your own code for building `dataset`. For example:
dataset = tf.data.TFRecordDataset(...)  # A dataset of tf.string records.
dataset = dataset.map(...)  # Extract components from each tf.string record.

# Choose a value of `max_elems` that is at least as large as the dataset.
max_elems = np.iinfo(np.int64).max
dataset = dataset.batch(max_elems)

# Extracts the single element of a dataset as one or more `tf.Tensor` objects.
# No iterator needed in this case!
whole_dataset_tensors = tf.contrib.data.get_single_element(dataset)

# Create a session and evaluate `whole_dataset_tensors` to get arrays.
with tf.Session() as sess:
    whole_dataset_arrays = sess.run(whole_dataset_tensors)

我收到一条错误消息，说明列 - no_semesters不能为空。为什么不设置为6的默认值？

这是声明 -

INSERT INTO PREMIERD08/PGM (PGM_ID, PGM_NAME) 
VALUES('CPD', 'COMPUTER   PROGRAMMING')

Answer 1

您的代码在Db2中运行（对于LUW） - 唯一要改变的是表名需要在“”中，因为/

CREATE TABLE "PREMIERD08/PGM" .....

INSERT INTO "PREMIERD08/PGM" (PGM_ID, PGM_NAME) 
VALUES('CPD', 'COMPUTER   PROGRAMMING')

sql-非默认值，检查约束

1 个答案: