Yes, something like this: As other answers have pointed out, MySQL also has the IF() function to do this using less verbose syntax. I generally try to avoid this because it is a MySQL-specific extension to SQL that isn’t generally supported elsewhere. CASE is standard SQL and is much more portable across different database engines, and I prefer to … Read more
VARCHAR is variable-length. CHAR is fixed length. If your content is a fixed size, you’ll get better performance with CHAR. See the MySQL page on CHAR and VARCHAR Types for a detailed explanation (be sure to also read the comments).
Single quotes are escaped by doubling them up, just as you’ve shown us in your example. The following SQL illustrates this functionality. I tested it on SQL Server 2008: Results
Quite simple actually: The % is a wildcard for any characters set (none, one or many). Do note that this can get slow on very large datasets so if your database grows you’ll need to use fulltext indices.
Rather slow, but working method to include any of words: If you need all words to be present, use this: If you want something faster, you need to look into full text search, and this is very specific for each database type.
Group By X means put all those with the same value for X in the one group. Group By X, Y means put all those with the same values for both X and Y in the one group. To illustrate using an example, let’s say we have the following table, to do with who is attending what subject at … Read more
In your table dbo.Sup_Item_Cat, it has a foreign key reference to another table. The way a FK works is it cannot have a value in that column that is not also in the primary key column of the referenced table. If you have SQL Server Management Studio, open it up and sp_help ‘dbo.Sup_Item_Cat‘. See which column that FK … Read more
Try this (in the psql command-line tool): See the manual for more info.
You need to alias the subquery. or to be more explicit
You don’t have full joins in MySQL, but you can sure emulate them. For a code sample transcribed from this Stack Overflow question you have: With two tables t1, t2: The query above works for special cases where a full outer join operation would not produce any duplicate rows. The query above depends on the UNION set operator to remove duplicate rows introduced by the query pattern. … Read more