MySQL create table if not exists and insert record only if table was created
Combine the creation and insert into a single statement: If it doesn’t create the table, AS SELECT … clause is ignored.
Database
MySQL Error “Operand should contain 1 column”
2 This question already has answers here: Operand Should Contain 1 Column – MySQL NOT IN (3 answers) Closed 7 years ago. I could find a lot of similar questions but no real solution for my problem. My SQL query: The error code I receive is If I just use the query in the parentheses … Read more
What is this JavaScript “require”?
So what is this “require?” require() is not part of the standard JavaScript API. But in Node.js, it’s a built-in function with a special purpose: to load modules. Modules are a way to split an application into separate files instead of having all of your application in one file. This concept is also present in other languages … Read more
MySQL Error: : ‘Access denied for user ‘root’@’localhost’
Open and edit /etc/my.cnf or /etc/mysql/my.cnf, depending on your distribution. Add skip-grant-tables under [mysqld] Restart MySQL You should be able to log in to MySQL now using the below command mysql -u root -p Run mysql> flush privileges; Set new password by ALTER USER ‘root’@’localhost’ IDENTIFIED BY ‘NewPassword’; Go back to /etc/my.cnf and remove/comment skip-grant-tables Restart MySQL Now you will be able to login with the … Read more
QL Error: ORA-00933: SQL command not properly ended
Oracle does not allow joining tables in an UPDATE statement. You need to rewrite your statement with a co-related sub-select Something like this: For a complete description on the (valid) syntax of the UPDATE statement, please read the manual: http://docs.oracle.com/cd/E11882_01/server.112/e26088/statements_10008.htm#i2067715
Cannot add or update a child row: a foreign key constraint fails
You’re getting this error because you’re trying to add/update a row to table2 that does not have a valid value for the UserID field based on the values currently stored in table1. If you post some more code I can help you diagnose the specific cause.
MySQL “CREATE TABLE IF NOT EXISTS” -> Error 1050
Works fine for me in 5.0.27 I just get a warning (not an error) that the table exists;
When should I use CROSS APPLY over INNER JOIN?
Can anyone give me a good example of when CROSS APPLY makes a difference in those cases where INNER JOIN will work as well? See the article in my blog for detailed performance comparison: INNER JOIN vs. CROSS APPLY CROSS APPLY works better on things that have no simple JOIN condition. This one selects 3 … Read more
Conversion failed when converting date and/or time from character string while inserting datetime
There are many formats supported by SQL Server – see the MSDN Books Online on CAST and CONVERT. Most of those formats are dependent on what settings you have – therefore, these settings might work some times – and sometimes not. The way to solve this is to use the (slightly adapted) ISO-8601 date format that is supported by SQL … Read more