Uh! I almost felt like going back in time some ten years when I was writing kernel drivers for Windows :) This is excellent participation from experts like Marko and Brian. Is it better write a function Drop table and and pass table name as parameter to do this? In my opinion, I think it is expensive to go to a function from a stored procedure just to drop a table
SQLite Query Language: ALTER TABLE
If any views refer to table X in a way that is affected by the schema change, then drop those views using DROP VIEW and recreate them with whatever changes are necessary to accommodate the schema change using CREATE VIEW. If foreign key constraints are enabled when a table is renamed, then any REFERENCES clauses in any table (either the table being renamed or some other table) that refer to the table being renamed are modified to refer to the renamed table by its new name
PostgreSQL: Documentation: 9.1: ALTER TABLE
(This requires superuser privilege if any of the triggers are internally generated constraint triggers such as those that are used to implement foreign key constraints or deferrable uniqueness and exclusion constraints.) USER Disable or enable all triggers belonging to the table except for internally generated constraint triggers such as those that are used to implement foreign key constraints or deferrable uniqueness and exclusion constraints. The value of separating validation from initial creation is that you can defer validation to less busy times, or can be used to give additional time to correct pre-existing errors while preventing new errors
ALTER TABLE attempt failed, this explaination came through perfectly, tatero Log In or Register to post comments Preeti (not verified) on May 13, 2004 This is a very systematic solution given to a problem ususlly faced while migrating from Oracle to SQL 2000. To demonstrate this T-SQL activity, run the code that Listing 1 shows to create and populate the Orders2 and OrderDetails2 tables in the Northwind database
The orders in which these are executed are as follows: Table Functions Unique Constraints Check Constraints Indexes You must also edit this script to use your desired collation. Download all scripts and explanation here About Collation Consolidation At some time in your DBA career, you may find yourself in a position when you sit back and realize that your database collations have somehow run amuck, or are faced with the ever annoying CANNOT RESOLVE COLLATION message when trying to join data of varying collation settings
PostgreSQL: Documentation: 9.0: ALTER TABLE
(This requires superuser privilege if any of the triggers are internally generated constraint triggers such as those that are used to implement foreign key constraints or deferrable uniqueness and exclusion constraints.) USER Disable or enable all triggers belonging to the table except for internally generated constraint triggers such as those that are used to implement foreign key constraints or deferrable uniqueness and exclusion constraints. Because of this flexibility, the USING expression is not applied to the column's default value (if any); the result might not be a constant expression as required for a default
If you have file1.sql alter table t1 add col1 date; alter table t1 add col2 date; alter table t1 add col3 date; And col2 is present,when the script is run, the other two columns would be added to the table and the log would show the error saying "col2" already exists, so you should be ok
Question: how do I discern between "user-generated statistics" and "query optimizer generated statistics"? As a T-SQL "IF" statement would be ideal, because I want to make my alter table command conditional upon this
ADD A COLUMN TO A TABLE IN T-SQL
Also, while "IF" and "THEN" are reserved words in SSCE (for compatibility with the rest of the SQL world), they are not defined in the grammar available for SSCE
ALTER TABLE ADD COLUMN IF NOT EXISTS in SQLite - Stack Overflow
Our current workaround is to execute the ALTER TABLE statement and ignore any "duplicate column name" errors, just like this Python example (but in C++). In this way, when the software is started, it can check the database schema and, if needed, run your ALTER TABLE query, then increment the stored version
Alter Table Drop Column
Name: Email: Comment: Home Tuning Services Featured Articles How to cache stored procedure results using a hash key There are a lot of different design patterns that lend themselves to creating SQL Server Database Optimization Guide In the troubleshooting guide we went over the different physical bottlenecks that can Yet Another Temp Tables Vs Table Variables Article The debate whether to use temp tables or table variables is an old Using Union Instead of OR Sometimes slow queries can be rectified by changing the query around a bit. We obfuscate data as it is moved to another environment and rather than updating the data it was actually much quicker to drop the column and add it back along with a default value
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