检查SQL Server数据库表中是否存在表或列

Question

Before I create a column or table in a SQL Server database I want to check if the required table and/or columns exist.

I have searched around and found 2 ways so far.

1. Stored procedures, which I don't want to use
2. By using the SqlCommand.ExecuteScalar() method and catching an exception to determine if the table/column exists, which for me is a work around but not a perfect solution.

Is there another way to check if table/column exists in SQL Server?

Answer 1

To check if a schema exists before creating it, you do the following:

To check if a column exists; you use IF NOT EXISTS and then put your actual query inside of that.

IF NOT EXISTS(SELECT * FROM sys.columns 
        WHERE [name] = N'columnName' AND [object_id] = OBJECT_ID(N'tableName'))
BEGIN
    ALTER TABLE ADD COLUMN MYCOLUMN
END

For a table, the query is a little similar :

IF (NOT EXISTS (SELECT * 
                 FROM INFORMATION_SCHEMA.TABLES 
                 WHERE TABLE_SCHEMA = 'TheSchema' 
                 AND  TABLE_NAME = 'TheTable'))
BEGIN
    CREATE TABLE MYTABLE
END

Answer 2

Query against the information_schema views :

select * 
from information_schema.columns
where column_name = @mycolumn
    and table_name = @mytable