Constant special item ID list CSIDL values provide a way to identify folders that applications use frequently but may not have the same name or location on any given computer. Variables that are processed for the operating system and in the context of each user.
Variables that are recognized only in the user context. You can use these variables within sections in the. You can use these variables in the. Skip to main content. This browser is no longer supported. Download Microsoft Edge More info.
Contents Exit focus mode. Is this page helpful? Please rate your experience Yes No. Any additional feedback? Submit and view feedback for This product This page. View all page feedback. In this article. The following script creates a small test table and populates it with 26 rows.
The script uses a variable to do three things:. To declare more than one local variable, use a comma after the first local variable defined, and then specify the next local variable name and data type. The scope of a variable is the range of Transact-SQL statements that can reference the variable. The scope of a variable lasts from the point it is declared until the end of the batch or stored procedure in which it is declared.
For example, the following script generates a syntax error because the variable is declared in one batch and referenced in another:. Variables have local scope and are only visible within the batch or procedure where they are defined. When a variable is first declared, its value is set to NULL. The first line of the file may be a header line which contains the name of each column.
CSV is unusual in that it encloses the entire field in double quotes if it contains the separator. However, If a repeated double-quote are the only two characters within the field, this indicates a field containing an empty string, which is quite different from NULL, signifying an unknown value. Because the rules are underspecified, different implementations diverge in their handling of edge cases.
You will find in some products that continuation lines are supported by starting the last field of the line with an un-terminated double-quote. Microsoft, surprisingly, sometimes has incompatible versions of CSV files between its own applications, and has even had incompatible CSV files in different versions of the same application. There is a good formal grammar for producing a CSV reader or writer here. This sort of mistake is common to find, but It is not the CSV convention that is at fault, but the implementation.
The easiest way to test, and often break, a poor implementation of CSV is to put the linefeed characters into a string value.
With BCP, its defects are even less subtle. Even putting a comma into a properly delimited string breaks the import. There is a great difference between a NULL and an empty string. Yes, it is correct. You can see that the people who devised the ConvertTo-CSV cmdlets played safe by delimiting every variable, which is fine but slightly more verbose than strictly necessary.
This has become a cult application with websites dedicated to its use. Basically, it can treat any text-based data file, whether XML, CSV, tab-delimited or whatever, as a single-table database. This can be run at the command line, or automated via COM.
It is fast and reliable. This is fine, and you can alter the provider connection string in a number of ways to specify whether it is tab delimited or CSV, and whether there are headers in the file or not.
Why are you trying to write to a file from T-SQL? Resist the urge to turn SQL Server into a scripting platform. I had problem in this subject, so I want to propose what I did. I Declared a Cursor for Select results and then I write them to file. For example:. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow.
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