Submitted by: Rafael Dipold (dipold)

I have a local database with 1.2 million "PARCEIROS" records. The NOME is a index column declared as:

NOME VARCHAR(50) CHARACTER SET ISO8859_1 NOT NULL COLLATE PT_BR

Using ibexpert, there are substancial performance difference using LIKE between 1 and 2 SQL modes above with same PLAN:

**STARTING doesn´t occur the same problem.

-----------------------------------------
--1. When I Inform 'RAFAEL%' in SQL inline
-----------------------------------------
SELECT NOME
FROM PARCEIROS
WHERE (NOME LIKE 'RAFAEL%')
ORDER BY NOME
-----------------------------------------
Plan
PLAN (PARCEIROS ORDER K_PARCEIROS_NOME_ASC)

------ Performance info ------
Prepare time = 16ms
Execute time = 16ms
Avg fetch time = 0,70 ms
Current memory = 21.836.360
Max memory = 25.249.672
Memory buffers = 2.048
Reads from disk to cache = 1.911
Writes from cache to disk = 0
Fetches from cache = 6.043

-----------------------------------------
--2. When I Inform 'RAFAEL%' in the NOME param
-----------------------------------------
SELECT NOME
FROM PARCEIROS
WHERE (NOME LIKE :NOME)
ORDER BY NOME
-----------------------------------------
Plan
PLAN (PARCEIROS ORDER K_PARCEIROS_NOME_ASC)

------ Performance info ------
Prepare time = 31ms
Execute time = 15s 156ms
Avg fetch time = 658,96 ms
Current memory = 24.125.112
Max memory = 25.249.672
Memory buffers = 2.048
Reads from disk to cache = 926.161
Writes from cache to disk = 1
Fetches from cache = 2.992.118