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Omnidex Queries and SQL Syntax

Clauses

DISTINCT

Distinct can be applied to an entire select-item list or used within an aggregate function.

SELECT DISTINCT city, state FROM prospects
SELECT count(DISTINCT zip_code) FROM prospects

Result Set Limiters

Result set limiters limit the rows returned by the select statement. The result set limiter processing is done AFTER the query has completed.

TOP n, EVERY n, RANDOM n

SELECT TOP 10 company FROM prospects
SELECT EVERY 20 company FROM prospects
SELECT RANDOM 10 company FROM prospects

These result set limiters do not order returned data in any way. Ordering is set by the ORDER BY clause.

Column name(s)

Column names from one or more tables.

SELECT company, contact, phone FROM customers
SELECT company, contact, order_date FROM customers, orders ...

Column name(s) with an alias

An alias containing a space or special character must be quoted. Single or double quotes.

The AS keyword is optional.

SELECT company CO, contact 'Contact Name', phone "Phone Number" FROM ...
SELECT contact AS 'Contact Name', phone AS 'Phone #' FROM ...

Table-qualified column name(s)

SELECT customers.company, customers.contact, orders.order_date
  FROM customers, orders ...

Table-alias qualified column name(s)

SELECT A.company, A.contact, B.order_date FROM company A, orders B ...

Aggregate Functions

min() max() avg() sum() count() count(*)

SELECT customer_no, min(amount), max(amount), avg(amount)
  FROM orders GROUP BY customer_no
SELECT company, sum(amount) FROM ...
SELECT count(*), count(state) FROM ...

SQL92-Compliant Functions

These functions can be used on literals or columns.

CASE
CAST
CHARACTER_LENGTH | CHAR_LENGTH
Concatenation using ||
CURRENT_DATE
CURRENT_TIME
CURRENT_TIMESTAMP
CURRENT_USER
EXTRACT
LOWER
POSITION
SESSION_USER
SUBSTRING
SYSTEM_USER
TRIM
UPPER
USER
SELECT upper(company), upper(contact), current_date FROM ...
SELECT position('SYS' IN 'DYNAMIC INFORMATION SYSTEMS'), system_user FROM ...

Omnidex Extended Functions

Extended Functions

These functions can be used on literals or columns

Function Description
$COL_LEN Return the length of a column as defined in the environment catalog.
$COLUMN_LENGTH Return the length of a column as defined in the environment catalog.
$CONTAINS | | | $CONTEXT | Return snippets of text from data qualified in a $CONTAINS function. | | $CONVERT | Convert a scalar expression from one data type to another. | | $CURRENT_ROW | Return the current row number. | | $EXTERNAL | Execute an external user-defined function. | | $IFNULL | Specify a return value for columns containing null values. | | $LJ | Left justify a string by eliminating leading white space. | | $LOOKUP | Retrieve textual metadata. | | $LPAD | Add leading "PAD" characters to a string. | | $MOD | Return "n modulus y" (remainder). | | $PROPER | Shift the first letter of each word in a string to upper case and all other letters to lower case. | | $RANDOM | Return a pseudo-random number. | | $RJ | Right justify a string by eliminating trailing white space and inserting leading spaces as needed. | | $ROUND | Round a numerical value to the specified number of decimal places. | | $RPAD | Add trailing "PAD" characters to a string. | | $SCORE | Returns the rank/relevancy score of qualified text from a $CONTAINS function. | | $SOUNDEX | Return the Soundex equivalent to a character string. | | $TRUNC | Return a numeric expression truncated to a specified number of digits to the right of the decimal point. | SELECT $proper(company), $random(3) FROM ... SELECT $soundex('database') FROM ... ==== Literals ==== SELECT 'Company Name: ', company, 'Contact Name: ', contact FROM ... ==== Expressions ==== SELECT order_number, 'Discount: ', (quantity * amount)*.02 FROM ... ==== $ROWID, $ODXID ==== $ROWID returns the internal rowid. This is either the native rowid or the redefined rowid. $ODXID is the Omnidex ID from the Omnidex indexes. SELECT $ROWID, $ODXID, Company FROM ... ==== * (Asterisk) ==== SELECT * FROM CUSTOMERS ... SELECT c.*, o.* FROM CUSTOMERS c, ORDERS o ... ==== Nested Select Statement ==== SELECT STATE, DESCRIPTION, (SELECT SUM(TOTAL) FROM ORDERS WHERE TAX_STATE='CO') FROM STATES WHERE STATE='CO' ====== Quick Links ====== ^ [[:start|Quick Links
General Programs Interfaces General Topics Miscellaneous Items
Omnidex Introduction OdxSQL ODBC Grids Release Notes
Administrating Omnidex (OdxAdmin) OdxNet JDBC Union Views Server Installs
Data and Index Design OdxAim Stored Procedures Rollup Tables Licensing
Omnidex Queries & SQL DBInstal OmniAccess Partitioning Settings
Active Counts OaComp/decomp/helper Client OA Explain Plans Glossary
PowerSearch DSEdit/OdxQuery RDBMS Indexing Debugging Appendix

© Copyright Dynamic Information Systems - This document was last updated July 15, 2009.


 
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sql/intro.1247784947.txt.gz · Last modified: 2012/10/26 14:21 (external edit)