Shulou(Shulou.com)06/01 Report--

VoicePortal=# create table testindex (no serial primary key, value integer)

NOTICE: CREATE TABLE will create implicit sequence "testindex_no_seq" for serial column "testindex.no"

NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "testindex_pkey" for table "testindex"

VoicePortal=# insert into testindex (value)

VoicePortal-# select trunc (random () * 10) from generate_series (1mem1000); random () produces a number of 0.1 *, where 10 is a number less than ten.

INSERT 0 1000 generates a thousand random numbers up to 10 and inserts them into testindex as value values

VoicePortal=# select * from testindex limit 10

No | value

-- +-

| 1 | 0 |

2 | 8

3 | 3

4 | 2

5 | 8

6 | 9

7 | 6

8 | 5

9 | 9

10 | 9

(10 rows)

So testindex's table is built and you can use it for testing.

VoicePortal=#\ d testindex

Table "public.testindex"

Column | Type | Modifiers

-+-

No | integer | not null default nextval ('testindex_no_seq'::regclass)

Value | integer |

Indexes:

"testindex_pkey" PRIMARY KEY, btree (no) automatically index

Flow out details of a table.

VoicePortal=#\ di+ testindex_pkey look up the index size of the table

List of relations

Schema | Name | Type | Owner | Table | Size | Description

-+-

Public | testindex_pkey | index | postgres | testindex | 40 kB |

(1 row)

VoicePortal=#\ dt+ testindex look up the table size

List of relations

Schema | Name | Type | Owner | Size | Description

-+-

Public | testindex | table | postgres | 64 kB |

(1 row)

Now that there are 1000 pieces of data in testindex, I'll add another 1000 to it.

VoicePortal=# insert into testindex VALUES ('1001)

INSERT 0 1

VoicePortal=# select count (*) from testindex

Count

1001

(1 row)

VoicePortal=# insert into testindex (value)

Select trunc (random () * 10) from generate_series (1002Jing 1100)

INSERT 0 99

VoicePortal=# insert into testindex (value)

VoicePortal-# select trunc (random () * 10) from generate_series (1101 ~ 2000)

INSERT 0 900

VoicePortal=#\ di+ testindex_pkey

List of relations

-[RECORD 1]-

Schema | public

Name | testindex_pkey

Type | index

Owner | postgres

Table | testindex

Size | 64 kB

Description |

VoicePortal=#\ dt+ testindex

List of relations

-[RECORD 1]-

Schema | public

Name | testindex

Type | table

Owner | postgres

Size | 96 kB

Description |

Delete some more data

VoicePortal=# delete FROM testindex where value

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.