Informix Cannot Create Unique Index On Column With Duplicate Data
Setup This example was tested against IDS version 11.10 running on 64-bit Linux x86. st_geometry_ops specifies the operator class. I always have Primary Keys, even in relationship tables ( the mid-table / connection table ) I might have them. Postgresql allows multiple NULL values to be in UNIQUE column, PRIMARY KEY doesn't allow NULLs. http://pgexch.com/informix-cannot/informix-cannot-get-supported-data-types-database-connection.html
share|improve this answer edited Jan 28 '09 at 13:07 answered Jan 28 '09 at 12:20 Jonas Lincoln 6,26062642 THAT scares the hell out of me (first quote). The clause cannot use any aggregate function. It is possible to make a unique index on mutiple columns. Some interesting facts about functional R-Tree indexes are: They are not bounding-box-only indexes; the leaf pages store the data objects themselves. http://www.oninit.com/errorcode/index.php?pageid=-371
Specifying Modes for Unique Indexes You must observe the following rules when you specify modes for unique indexes in CREATE INDEX statements: You can set the mode of a unique index Join them; it only takes a minute: Sign up Primary key or Unique index? In this query, st_intersects, st_centroid, and st_envelope are provided by the Spatial DataBlade st_envelope computes the bounding box of each tsunami line, returning type st_multilinestringst_centroid computes the center of each city, Besides that, it's just theory.
Refer to the makeinc.* files in $INFORMIXDIR/incl/dbdk for examples of appropriate compiler and linker options for your platform. Then it says "Enter Column Name". Browse other questions tagged sql database database-design or ask your own question. An index associates the location of a row in the database with an ordered subset of the data and/or a derivative of the data.
There are no significant differences between creating a UNIQUE constraint and creating a unique index that is independent of a constraint. SQLSTATE=23515Could you please suggest how to solve this problem?Thank you and Best regards,Jaturong Jaturong Phewphet February 19, 2008 at 11:01 AM 0 Likes 4 replies Share & Follow Privacy Terms of The nodes of the index initially fill to a certain percentage and contain space for inserts. http://www.baanboard.com/baanboard/showthread.php?t=9862 Sometimes a query can be satisfied by examining the index only, without fetching any tuples from the table.
you cannot use the CLUSTER option and storage options in the same CREATE INDEX statement. set explain on directs IDS to generate a file that shows the query plan. Database Object Name, p. 4-50 The following limitations apply to the expression in the GK SELECT clause: The expression cannot refer to any SPL routine. As an example, I have the following tables: CREATE TABLE toll_booths ( id INTEGER NOT NULL PRIMARY KEY, name VARCHAR(255) NOT NULL, ...
Specifying Modes for Duplicate Indexes You must observe the following rules when you specify modes for duplicate indexes in CREATE INDEX statements: You can set a duplicate index to enabled or https://quickview.cloudapps.cisco.com/quickview/bug/CSCuo51115 This is my experience having seen and managed or queried data from or imported data from hundreds of databases that store data about many differnt types of information. –HLGEM Aug 20 Yes No Additional feedback? 1500 characters remaining Submit Skip this Thank you! And if there's no natural pk, I add a column and a sequence and a trigger and all because ____?
CREATE CLUSTER INDEX c_clust_ix ON customer (zipcode) This statement creates an index on the customer table that physically orders the table by zip code. http://pgexch.com/informix-cannot/informix-cannot-write-blob.html User must be a member of the sysadmin fixed server role or the db_ddladmin and db_owner fixed database roles.Using SQL Server Management StudioTo create a unique index by using the Table ENABLED The database server updates the index after insert, delete, and update operations that modify the base table. When multiple columns are listed, the concatenation of the set of columns is treated as a single composite column for indexing.
You might need to join the violations and diagnostics tables to get all the necessary information. locates and deletes the duplicates; and 3. I'm a bit surprised by your words, as I though using integer keys or more natural keys like short VARCHAR, would likely makes just a tiny difference as hashing is used navigate here This means that lookups are much faster on the primary key because it doesn't have to do any dereferencing as it has to do with any other kind of index.
Hopefully by seeing the various ways that functional indexes are created and used, you will be able to use them to improve the performance of your query searches. Barth Jan 28 '09 at 19:35 2 You only need a primary key if you're going to have children. CREATE FUNCTION circleArea( radius FLOAT ) RETURNS float WITH (NOT VARIANT); RETURN 3.14159 * radius * radius; END FUNCTION; Create a functional index on the area of the circle.
Refer to your IDS documentation for complete information regarding optimizer-related SQL directives.
He currently works on the SQL Optimizer component of the IBM Informix Dynamic Server. 06 December 2007 Also available inChinese Table of contents Introduction Benefits of a functional index Various types I would not use them nmost of the time. A functional index can be created on user defined types. http://pgexch.com/informix-cannot/informix-cannot-locate-service-tcp.html An appropriate index is one that indexes the same columns that are used in the primary-key, referential or unique constraint.
UNIQUE(license_plate) ) CREATE TABLE drive_through ( id INTEGER NOT NULL PRIMARY KEY, toll_booth_id INTEGER NOT NULL REFERENCES toll_booths(id), vin VARCHAR(17) NOT NULL REFERENCES cars(vin), at TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL, amount For a discussion of the GLS aspects of the CREATE INDEX statement, see the Informix Guide to GLS Functionality. For information about operator classes, refer to the CREATE OPCLASS statement In this example, the name is sbsp2. For performance implications of globally-detached indexes, see your Performance Guide.