Omnidex SQL: CREATE TABLE

Description | Syntax | Topics | Examples

CREATE ENVIRONMENT and CREATE DATABASE have to be specified before specifying CREATE TABLE.

The IN “filespec.xml” clause has to be specified after the column definitions.

Tables must be declared in order of their constraints.

Parent tables should be declared before children tables.

Most CREATE TABLE statements will typically look like the following example where Omnidex indexing is specified after the column_name and column_type.

CREATE TABLE mytable
  PHYSICAL "mydir/mytable.dat"
  (
    user_id         INTEGER         OMNIDEX,
    region          CHARACTER(2)    OMNIDEX,
    full_name       CHARACTER(30)   QUICKTEXT,
    address         CHARACTER(60)   QUICKTEXT,
    city            CHARACTER(30)   QUICKTEXT,
    state           CHARACTER(2)    OMNIDEX
  )
in "simple.xml";

create table "HOUSEHOLDS"
  physical   "dat/households*.dat"
  (
   "HOUSEHOLD"    character(12),
   "ADDRESS"      character(50),
   "CITY"         character(28),
   "STATE"        character(2),
   "ZIP"          character(5),
   "COUNTRY"      character(2),
   constraint HOUSEHOLD_HOUSEHOLD_PK primay ("HOUSEHOLD"),
   constraint HOUSEHOLD_STATE_fk FOREIGN ("STATE") references "states",
   constraint HOUSEHOLDS_COUNTRY_FK foreign ("COUNTRY") references "COUNTRIES"
  )
 in "simple.xml";
 

Here is the same CREATE TABLE statement as above but with the Omnidex Index type specified for each column.

create table "HOUSEHOLDS"
  physical   "dat/households*.dat"
  (
   "HOUSEHOLD"    character(12)     omnidex,
   "ADDRESS"      character(50)     quicktext,
   "CITY"         character(28)     quicktext,
   "STATE"        character(2)      omnidex,
   "ZIP"          character(5)      omnidex,
   "COUNTRY"      character(2)      omnidex,
   constraint HOUSEHOLD_HOUSEHOLD_PK primay ("HOUSEHOLD"),
   constraint HOUSEHOLD_STATE_fk FOREIGN ("STATE") references "states",
   constraint HOUSEHOLDS_COUNTRY_FK foreign ("COUNTRY") references "COUNTRIES"
 )
 in "simple.xml";
 

Here is the same CREATE TABLE statement as above but with the Omnidex Index type specified for each column.

Additionally, it creates an Omnidex Composite index and combines the STATE and CITY columns into a single index.

create table "HOUSEHOLDS"
  physical   "dat/households*.dat"
  (
   "HOUSEHOLD"    character(12)     omnidex,
   "ADDRESS"      character(50)     quicktext,
   "CITY"         character(28)     quicktext,
   "STATE"        character(2)      omnidex,
   "ZIP"          character(5)      omnidex,
   "COUNTRY"      character(2)      omnidex,
   constraint HOUSEHOLD_HOUSEHOLD_PK primay ("HOUSEHOLD"),
   constraint HOUSEHOLD_STATE_fk FOREIGN ("STATE") references "states",
   constraint HOUSEHOLDS_COUNTRY_FK foreign ("COUNTRY") references "COUNTRIES"
   omnidex index "HSHD_STATE_CITY" ("STATE","CITY")
 )
 in "simple.xml";
 

There are three types of Omnidex indexes called Omnidex, QuickText, and FullText.

The following table shows the key types of retrieval properties of these Omnidex index types.

In addition to the three basic Omnidex Index Types: Omnidex, QuickText, and FullText, there is a Custom Index Type that can be used to specify advanced indexing options.

Omnidex supports the following standard datatypes:

Omnidex also provides partial support for National Character Datatypes (sometimes called Unicode datatypes or wide characters). The Omnidex SQL Engine will process these datatypes, but the Omnidex Indexing Engine will only index the lower 8 bits of these datatypes.

1. Generally Omnidex indexes should be put on the Parent primary key and the child foreign key.
2. Create a composite index for group bys of multiple columns.
3. Create a composite index of all group by columns plus the aggregate columns.
4. Create a composite index of group bys in order of reduced cardinality
5. consider a catch all index of all group by and metric columns
6. add a foreign key to the composite index when grouping on a column in the snowflaked table.