PGConf.ASIA Lightning Talk(2016-12-03)

pg_reversiぬこ＠横浜 (@nuko_yokohama)

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Self-Introduction

Search with the word "PostgreSQL Ramen".

I'm "nuko_yokohama".I am aiming at PostgreSQL entertainer.

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The theme about today.

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Sorry, Useless knowledge

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Solutions for "Solitaire

employees"

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pg_reversi

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Reversi by PostgreSQL

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pg_reversi SQL Functions.

black(x, y)white(x,y)

black_pass()white_pass()

get_turn_boad_status()

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Implemented by Implemented by SQL/plpgsql.SQL/plpgsql.

Because, I do not want to Because, I do not want to implemented by implemented by

C language!C language!絶対に C言語で書きたくないでござる！

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Viewer is implemented psql

script file.(Used PostgreSQL 9.6

feature “\crosstabview”)

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Viewer script file.SELECT get_turn_boad_status() AS status;\o /dev/nullSELECT x AS " ", y, CASE WHEN status = 1 THEN '●' WHEN status = -1 THEN '○' ELSE ' ' END AS statusFROM boad ORDER BY x;\o\crosstabview " " y status y

Point. SELECT result output to /dev/null

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pg_reversi image

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pg_reversiDemonstration

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Able to play Reversi with psql!

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Up to this point is the explanation of the "Standard edition".

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pg_reversiEnterprise Edition

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FeaturesBy emit_log_hook, to conceal the SQL

log from pg_reversi application.static voidpg_reversi_emit_log_hook(ErrorData *data) { const char* appname = application_name;

if (appname == NULL || *appname == '\0') { /* applicatoin_name is no set */ return ; }

if (!strcmp(appname, "pg_reversi")) { /* When application_name is pg_reversi, output to the server log is suppressed. */ data->output_to_server = false; } return ;}

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Setting the pg_reversi to PostgreSQL setting "preload_shared_libraries'.

preload_shared_libraries = 'pg_reversi'

In psql not, use the "pg_reversi" utility (psql copy).

$ pg_reversi -U postgres pg_reversi

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Show “application_name”$ psql -U postgres pg_reversi -c "SHOW application_name" application_name ------------------ psql(1 row)

$ pg_reversi -U postgres pg_reversi -c "SHOW application_name" application_name ------------------ pg_reversi(1 row)

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Enterprise EditionDemonstration

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Standard Edition

Since SQL is output to the Since SQL is output to the server log, the DBA will server log, the DBA will

check it!check it!↓↓

My boss gets angry!My boss gets angry!

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Enterprise EditionSQL is not logged.SQL is not logged.

↓↓DBA and Boss also does DBA and Boss also does

not notice. not notice. Everyone is happy.Everyone is happy.

Win-Win!Win-Win!

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Exactly, feature for Exactly, feature for "Lazy employee in "Lazy employee in

Enterprise company".Enterprise company".

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Conclusion

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Reversi can also be played.

(It can not be used with pgAdmin4!)

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Only on the Only on the PostgreSQL….PostgreSQL….

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End.