visual studio 2017 sql server data tools edit top 200

Editing Top 200 Rows in Visual Studio 2017 SQL Server Data Tools

When working with SQL Server data tools in Visual Studio 2017, you may encounter a common issue where your query returns empty string values instead of NULL. This can be frustrating and make it difficult to handle the data correctly. In this article, we will discuss how to deal with empty string values and provide a custom function to handle such cases.

To begin with, let's create a function that checks if an input value is NULL or not. We can do this by creating a scalar-valued function called `IsEmpty`. This function will return 1 if the input value is NULL and 0 otherwise.

```sql

CREATE FUNCTION isEmpty (@value nvarchar(50))

RETURNS int

BEGIN

IF @value IS NULL

RETURN 1

ELSE

RETURN 0

END

```

Once we have created this function, we can use it to check if a value is empty or not. For example, let's say we want to update a column with a default value of 'NewValue' when the input value is NULL. We can use the `ISNULL` and `COALESCE` functions to achieve this.

```sql

UPDATE table_A

SET column_A = COALESCE(column_A, 'NewValue')

WHERE isEmpty(column_A) = 1;

```

In this example, if the value of `column_A` is NULL, it will be updated with 'NewValue'. If the value is not NULL, it will remain unchanged.

However, what happens when we encounter an empty string value instead of a NULL? Unfortunately, there is no 'magic' formula to handle this situation. We need to think creatively and find a solution that works for our specific use case.

One approach is to use the `NULLIF` function to replace the empty string with NULL. For example:

```sql

UPDATE table_A

SET column_A = NULLIF(column_A, '')

WHERE isEmpty(column_A) = 1;

```

This will update all rows where `column_A` is an empty string and set it to NULL.

Another approach is to use a custom function that checks if the input value is an empty string or not. We can create a user-defined scalar-valued function called `IsEmptyString` that returns 1 if the input value is an empty string and 0 otherwise.

```sql

CREATE FUNCTION IsEmptyString (@value nvarchar(50))

RETURNS int

BEGIN

IF @value = ''

RETURN 1

ELSE

RETURN 0

END

```

We can then use this function to check if a value is an empty string or not. For example:

```sql

UPDATE table_A

SET column_A = COALESCE(column_A, 'NewValue')

WHERE IsEmptyString(column_A) = 1;

```

In this example, if the value of `column_A` is an empty string, it will be updated with 'NewValue'. If the value is not an empty string, it will remain unchanged.

In conclusion, handling empty string values in SQL Server data tools can be challenging, but there are several approaches we can take to deal with this issue. By creating custom functions and using built-in functions like `ISNULL`, `COALESCE`, and `NULLIF`, we can effectively handle empty string values and ensure that our data is accurate and reliable.

Visual studio 2017 sql server data tools edit top 200