Double quotation marks in SQL

In SQL, 'single quotes are used to represent strings. To include 'single quotes, You must escape them. Therefore, you can see ''' to represent a 'string. In this way, all the numbers in the SQL statement are enclosed in single quotes. If a connection is involved, '+ "..." +' is used'

For example:

Declare @ strcondition nvarchar (3000)

Set @ strcondition = @ strcondition + 'and (userquestion. topic like ''% '+ @ key +' %'' or userquestion. content like ''' % '+ @ key +' % '')'

 

Declare @ dd nvarchar (30)

Declare @ con nvarchar (3000)

Declare @ clubid int

Set @ con = 'userid in' + '(select * from # temp)' + 'and. clubid = '+ STR (@ clubid) +' and. rolename = @ dd

 

Exec ('delete [DBO]. [AAA] Where messageid in ('+ @ IDs + ')')