Drop a temporary table if it exists
From SQL Server 2016 you can just use On previous versions you can use You could also consider truncating the table instead rather than dropping and recreating.
SQL
MySQL Cannot Add Foreign Key Constraint
To find the specific error run this: And look in the LATEST FOREIGN KEY ERROR section. The data type for the child column must match the parent column exactly. For example, since medicalhistory.MedicalHistoryID is an INT, Patient.MedicalHistory also needs to be an INT, not a SMALLINT. Also, you should run the query set foreign_key_checks=0 before running the DDL so you can create the tables in an … Read more
How to rename a table in SQL Server?
To rename a table in SQL Server, use the sp_rename command:
SqlException: DB2 SQL error: SQLCODE: -302, SQLSTATE: 22001, SQLERRMC: null
You can find the codes in the DB2 Information Center. Here’s a definition of the -302 from the z/OS Information Center: THE VALUE OF INPUT VARIABLE OR PARAMETER NUMBER position-number IS INVALID OR TOO LARGE FOR THE TARGET COLUMN OR THE TARGET VALUE On Linux/Unix/Windows DB2, you’ll look under SQL Messages to find your error message. If the code is positive, … Read more
ORA-01843 not a valid month- Comparing Dates
I have a problem when try to select data from a table filtering by date. For example: The Oracle Error is: Probably the source data of table is corrupted, in this case: How can i solve this problem? Can I change this dates for null? The results of this select, select * from nls_session_parameters; , is:
Finding duplicate values in a SQL table
Simply group on both of the columns. Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY but this has changed with the idea of “functional dependency”: In relational database theory, a functional dependency is a constraint between two sets of attributes in a relation from a database. In other words, … Read more
How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
One-to-one: Use a foreign key to the referenced table: You must also put a unique constraint on the foreign key column (addess.student_id) to prevent multiple rows in the child table (address) from relating to the same row in the referenced table (student). One-to-many: Use a foreign key on the many side of the relationship linking back … Read more
How to declare a variable in MySQL?
There are mainly three types of variables in MySQL: User-defined variables (prefixed with @):You can access any user-defined variable without declaring it or initializing it. If you refer to a variable that has not been initialized, it has a value of NULL and a type of string.SELECT @var_any_var_name You can initialize a variable using SET or SELECT statement:SET @start = 1, @finish = … Read more
T-SQL split string based on delimiter
May be this will help you.
IDENTITY_INSERT is set to OFF – How to turn it ON?
Should you instead be setting the identity insert to on within the stored procedure? It looks like you’re setting it to on only when changing the stored procedure, not when actually calling it. Try: