Comparison of different SQL implementations
Instead, a MSSQL 2000-specific syntax was needed: SELECT TOP n columns FROM tablename ORDER BY key ASC The TOP construct is still available in MSSQL 2008, and it's handy for casual SQL work. Standard Optional feature T171 defines LIKE clause in table definition: CREATE TABLE t2 ( LIKE t1 ) The DBMS may support an extension of this (feature T173) which allows for more table properties to be copied: CREATE TABLE t2 ( LIKE t1 INCLUDING IDENTITY INCLUDING DEFAULTS INCLUDING GENERATED ) If INCLUDING DEFAULTS is not specified, column defaults will not be part of t2; likewise with IDENTITY and GENERATED properties
How to Delete Data From a DB2 Table and Release Disk Space - db2commerce.com
I used this method for the same delete I was running for about 7 million rows in the STAGLOG table, and it completed in less than an hour what had been taking days - so it's at least an order of magnitude faster. Reorg the Table After your delete is complete, assuming you're using AST tablespaces (DMS are similar), you will not see any change in the amount of space taken up in your filesystem
Create a Modified On Column in SQL Server - CodeProject
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Default Value for TIMESTAMP in DB2
I am sure some of you have found your ways using .NET CLR programming within SQL; however, this article aims to show you how to easily do so using T-SQL syntax. Generally, such a connection is created by the host server or PC having two or more network cards installed and each having an IP address and subnet mask from a different IP address range
FOR EACH ROW triggers are called once for each inserted, updated, or deleted row.QUEUE is implemented for syntax compatibility with HSQL and has no effect.The trigger need to be created in the same schema as the table. Currently, enabling this is experimental only.This is a global setting, which means it is not possible to open multiple databases with different modes at the same time in the same virtual machine
DB2 vs MySQL - performance on large tables - DB2 Database
Browse more DB2 Database Questions on Bytes Question stats viewed: 20219 replies: 57 date asked: Nov 12 '05 Follow this discussion Similar topics Help! Large table performance problem with MYSQL performance with ASP.NET Large table performance problem with MYSQL performance with ASP.NET can postgresql handle these large tables MySQL with large table. Should I assume MySQL does run much faster than DB2 on large tables? Could anyone advice? I wouldn't make that assumption - seems like you've only got a single data point here
It defines the identity column so that DB2 will always generate the values for the column and uses the default value, which is 1, for the first value that should be assigned and for the incremental difference between the subsequently generated consecutive numbers. CREATE TABLE CORP.DIVISION (DIVNUM CHAR(3) NOT NULL, DIVNAME VARCHAR(36) NOT NULL, MGR CHAR(6) , LOCATION CHAR(16) , PRIMARY KEY(DIVNUM) ) IN DSNMAIN.TS111; Example 2: The next example creates a table named CORP.PROJECTS in an implicitly created table space of the database DSNMAIN and assigns the table a validation procedure named DSNVAL
DB2 ensures that the constraint is not violated during inserts and updates.Suppose that you add a column to the BOOKS table for a book type, and the values that you wish to allow are F (fiction) and N (nonfiction). A view essentially is a name for a stored query that you can use much like a table.For example, suppose that a company has a table containing information about its employees
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DB2 10 Universal Table Space - 2012-03-18 - no template
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Since I DID only have one Unique Constraint, I knew which one to drop, but if I had more, I wouldn't know how to decide which Unique Constraint to drop. My problem is that if I had more than one Unique Constraint on my table (luckily, I did not), I would not know which Constraint to drop in order to drop my problematic Index
The columns should have the same names, data types, null attributes, CCSIDs, subtypes, hidden attributes, and field procedures as the corresponding system-period temporal table. The basis of temporal tables: The periodThe period is defined as two columns where the first column represents the beginning of the period and the second column represents the end of the period
It can take on these values: 0100Table has had column added 0110Table has VARCHAR 0000Table has fixed-length rows (even if compressed) So if it's set to 4, you need to REORG. For instance, I may have a table POLICY with these columns: POLNO CHAR(8) AMOUNT SMALLINT I can then add another column using ALTER TABLE: ALTER TABLE ADD CUSTNAME CHAR(32) so the table now has these columns: POLNO CHAR(8) AMOUNT SMALLINT CUSTNAME CHAR(32) Rows which already existed in the table are not changed, but take on the default value for the new column, so the new column must either be nullable, as in this case (because NOT NULL was not specified), or have a default specified when the column is added
DB2: Convert existing column to identity - Stack Overflow
IBM Data Movement Tool does this automatically but if you are not using the tool and want a way to sync up start value of the identity column with the data in your database, you can use this stored procedure to sync the data. So far I am able to do so very easily with the following: alter table list alter column id set generated always as identity (start with 0); Unfortunately, I need it to start at the maximum number of the data that is already in the table
How to add IDENTITY column to existing table - ChannelDB2
Following statements fails due to syntax error: alter table public.clicks add column id integer generated always as identity But i have good news for everyone
The result of the fullselect must provide a set of columns that match the columns in the existing table (same number of columns, same column definitions, and same names). We need to execute the DB2 LOAD utility to load values into this table in Test; however, the GENERATED ALWAYS clause forces DB2 to generate values for this column
The types of objects that can be created depends on which RDBMS is being used, but most support the creation of tables, indexes, users, synonyms and databases
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