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2025-04-02 Update From: SLTechnology News&Howtos shulou NAV: SLTechnology News&Howtos > Database >
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Shulou(Shulou.com)06/01 Report--
The best field order (conclusion: the later columns have more access to CPU)
Validation script 1 (construct tables and data first)
SET SERVEROUTPUT ON
SET ECHO ON
-construct a table T with 25 fields
DROP TABLE t
DECLARE
L_sql VARCHAR2 (32767)
BEGIN
L_sql: = 'CREATE TABLE t ('
FOR i IN 1..25
LOOP
L_sql: = l_sql | |'n' | | I | | 'NUMBER,'
END LOOP
L_sql: = l_sql | | 'pad VARCHAR2 (1000)) PCTFREE 10'
EXECUTE IMMEDIATE l_sql
END
/
-populate the record and this table T
DECLARE
L_sql VARCHAR2 (32767)
BEGIN
L_sql: = 'INSERT INTO t SELECT'
FOR i IN 1..25
LOOP
L_sql: = l_sql | | '0jue'
END LOOP
L_sql: = l_sql | | 'NULL FROM dual CONNECT BY level
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Continue with the installation of the previous hadoop.First, install zookooper1. Decompress zookoope
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