Обсуждение: Random Unique Id
Hi all,<br /> I was searching for a sequence (for serials) that let me use a random unique number ID on a Primary Key
ora simple index.<br /> I have not found a solution so I have done it by myself. I would like to share it so here it
is:<br/> <br />-- ----------------------------<br />-- Create language "plpgsql"<br />--
----------------------------<br/>CREATE LANGUAGE plpgsql;<br /><br />-- ----------------------------<br />-- Table
structurefor "public"."tarjeta"<br /> -- ----------------------------<br />drop table "public"."tarjeta";<br />CREATE
TABLE"public"."tarjeta"(<br />"idtarjeta" int8 NOT NULL DEFAULT randomuniqueidtarjeta(),<br />"fechaemision" timestamp
NOTNULL DEFAULT now(),<br /> "descripcion" varchar(255) ,<br />PRIMARY KEY ("idtarjeta")<br />) WITHOUT OIDS;<br /><br
/>------------------------------<br />-- Definition of function "randomuniqueidtarjeta"<br />--
----------------------------<br/><br />CREATE OR REPLACE FUNCTION randomUniqueIdTarjeta() RETURNS bigint AS $$<br /><br
/>DECLARE<br/><br /> -- SET THE KEY SIZE (IN CHARACTERS)<br /> idSize constant integer := 10;<br /><br />
sizeMultiplicatorconstant bigint := 10 ^ idSize;<br /><br /> loopLimit bigint := sizeMultiplicator * 4;<br />
randomNumberbigint;<br /> canIUseIt boolean := false;<br /><br />BEGIN<br /><br /> -- LOOP UNTIL FIND AN UNIQUE
RANDOMNUMBER OR FILL THE LOOP LIMIT<br /> WHILE ( not ( canIUseIt ) and ( loopLimit > 0) ) LOOP<br /><br />
-- CALCULATE A TEN DIGITS RANDOM NUMBER<br /> randomNumber := CAST ( ( random() * sizeMultiplicator ) AS
bigint);<br /><br /> -- VALIDATE THAT THE NUMBER WON'T START WITH 0<br /> IF ( (randomNumber >=
sizeMultiplicator/ 10 ) and ( randomNumber < sizeMultiplicator ) ) THEN<br /><br /> -- CHECK THAN RANDOM
NUMBERNOT EXISTS ON TABLE<br /> -- IMPORTANT!!! CHANGE WITH TABLE AND FIELD TO SEARCH FOR A DUPLICATATION<br
/> PERFORM idtarjeta FROM tarjeta WHERE idtarjeta = randomNumber;<br /> IF NOT FOUND THEN<br
/> canIUseIt = true;<br /> END IF;<br /><br /> END IF;<br /><br /> loopLimit =
loopLimit- 1;<br /><br /> END LOOP;<br /><br /> -- IF LOOP ENDS WITH A UNIQUE RANDOM NUMBER RETURNS THE NUMBER
CONCATENATEDWITH A VERIFICATION NUMBER ELSE RAISE AN EXCEPTION<br /> IF ( canIUseIt ) THEN<br /> RETURN
CAST( ( CAST ( randomNumber AS text ) || CAST ( verificationNumber( CAST (randomNumber AS text ) ) AS text ) ) AS
bigint) ;<br /> ELSE<br /> RAISE EXCEPTION 'Could not calculate a Random Unique ID on table Tarjeta.';<br />
END IF;<br /><br />END;<br />$$ LANGUAGE plpgsql;<br /><br />-- ----------------------------<br />-- Definition of
function "randomuniqueidtarjeta"<br />-- ----------------------------<br /><br />CREATE OR REPLACE FUNCTION
verificationNumber(idtext) RETURNS integer AS $$<br /> DECLARE<br /><br /> auxValue integer := 0;<br />
verifyArrayconstant integer[] :=ARRAY [5,4,3,2,7,6,5,4,3,2,1];<br /> verificationNumber integer := 0;<br /><br
/>BEGIN<br/><br /> -- ASK FOR ID LENGTH EQUAL TO 10 DIGITS. THE ALGORITHM WORKS ONLY FOR <br /> IF ( LENGTH( id
)<> 10 ) THEN<br /><br /> RAISE EXCEPTION 'Could not calculate a verification number. The ID must have 10
digits.';<br/><br /> ELSE<br /><br /> -- LOOP ON THE TEN DIGITS AND MULTIPLY WITH THE SAME POSITION ON
virifyArray<br/> FOR digit IN 1..10 LOOP<br /> auxValue = auxValue + ( CAST(SUBSTR(id, digit, 1) AS
int)* verifyArray[digit] );<br /> END LOOP;<br /><br /> -- CALCULATE THE VERIFICATION NUMBER<br />
verificationNumber= 11 - (auxValue % 11);<br /><br /> -- REPLACE THE TWO DIGITS VERIFICATION NUMBER<br />
IF( verificationNumber = 11 ) THEN<br /> RETURN 0;<br /> ELSEIF ( verificationNumber = 10 )
THEN<br/> RETURN 9;<br /> ELSE<br /> RETURN verificationNumber;<br /> END IF;<br
/><br/> END IF;<br /><br />END;<br />$$ LANGUAGE plpgsql;<br /><br />-- ----------------------------<br />-- INSERTs
toprobe the functions<br />-- ----------------------------<br /> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta
1');<br/>INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 2');<br />INSERT INTO tarjeta (descripcion) VALUES
('Tarjeta3');<br />INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 4');<br /> INSERT INTO tarjeta (descripcion)
VALUES('Tarjeta 5');<br />INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 6');<br />INSERT INTO tarjeta
(descripcion)VALUES ('Tarjeta 7');<br />INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 8');<br /> INSERT INTO
tarjeta(descripcion) VALUES ('Tarjeta 9');<br />INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 10');<br /><br /><br
/> It is my first post so sorry about the format of the SQL Dump and sorry about my english.<br /> Note:
thereis a second function that calculate a verification number like an argentinian code called CUIL (only available for
10digits numbers)<br /> Regards....<br /><br /> Nahuel Alejandro Ramos.<br /><br />
Nahuel Alejandro Ramos wrote:
> Hi all,
> I was searching for a sequence (for serials) that let me use a random
> unique number ID on a Primary Key or a simple index.
> I have not found a solution so I have done it by myself. I would like
> to share it so here it is:
>
> -- ----------------------------
> -- Create language "plpgsql"
> -- ----------------------------
> CREATE LANGUAGE plpgsql;
>
> -- ----------------------------
> -- Table structure for "public"."tarjeta"
> -- ----------------------------
> drop table "public"."tarjeta";
> CREATE TABLE "public"."tarjeta"(
> "idtarjeta" int8 NOT NULL DEFAULT randomuniqueidtarjeta(),
> "fechaemision" timestamp NOT NULL DEFAULT now(),
> "descripcion" varchar(255) ,
> PRIMARY KEY ("idtarjeta")
> ) WITHOUT OIDS;
>
> -- ----------------------------
> -- Definition of function "randomuniqueidtarjeta"
> -- ----------------------------
>
> CREATE OR REPLACE FUNCTION randomUniqueIdTarjeta() RETURNS bigint AS $$
>
> DECLARE
>
> -- SET THE KEY SIZE (IN CHARACTERS)
> idSize constant integer := 10;
>
> sizeMultiplicator constant bigint := 10 ^ idSize;
>
> loopLimit bigint := sizeMultiplicator * 4;
> randomNumber bigint;
> canIUseIt boolean := false;
>
> BEGIN
>
> -- LOOP UNTIL FIND AN UNIQUE RANDOM NUMBER OR FILL THE LOOP LIMIT
> WHILE ( not ( canIUseIt ) and ( loopLimit > 0) ) LOOP
>
> -- CALCULATE A TEN DIGITS RANDOM NUMBER
> randomNumber := CAST ( ( random() * sizeMultiplicator ) AS bigint );
>
> -- VALIDATE THAT THE NUMBER WON'T START WITH 0
> IF ( (randomNumber >= sizeMultiplicator / 10 ) and (
> randomNumber < sizeMultiplicator ) ) THEN
>
> -- CHECK THAN RANDOM NUMBER NOT EXISTS ON TABLE
> -- IMPORTANT!!! CHANGE WITH TABLE AND FIELD TO SEARCH FOR A
> DUPLICATATION
> PERFORM idtarjeta FROM tarjeta WHERE idtarjeta = randomNumber;
> IF NOT FOUND THEN
> canIUseIt = true;
> END IF;
>
> END IF;
>
> loopLimit = loopLimit - 1;
>
> END LOOP;
>
> -- IF LOOP ENDS WITH A UNIQUE RANDOM NUMBER RETURNS THE NUMBER
> CONCATENATED WITH A VERIFICATION NUMBER ELSE RAISE AN EXCEPTION
> IF ( canIUseIt ) THEN
> RETURN CAST ( ( CAST ( randomNumber AS text ) || CAST (
> verificationNumber( CAST (randomNumber AS text ) ) AS text ) ) AS
> bigint ) ;
> ELSE
> RAISE EXCEPTION 'Could not calculate a Random Unique ID on table
> Tarjeta.';
> END IF;
>
> END;
> $$ LANGUAGE plpgsql;
>
> -- ----------------------------
> -- Definition of function "randomuniqueidtarjeta"
> -- ----------------------------
>
> CREATE OR REPLACE FUNCTION verificationNumber(id text) RETURNS integer AS $$
> DECLARE
>
> auxValue integer := 0;
> verifyArray constant integer[] :=ARRAY [5,4,3,2,7,6,5,4,3,2,1];
> verificationNumber integer := 0;
>
> BEGIN
>
> -- ASK FOR ID LENGTH EQUAL TO 10 DIGITS. THE ALGORITHM WORKS ONLY FOR
> IF ( LENGTH( id ) <> 10 ) THEN
>
> RAISE EXCEPTION 'Could not calculate a verification number. The
> ID must have 10 digits.';
>
> ELSE
>
> -- LOOP ON THE TEN DIGITS AND MULTIPLY WITH THE SAME POSITION ON
> virifyArray
> FOR digit IN 1..10 LOOP
> auxValue = auxValue + ( CAST(SUBSTR(id, digit, 1) AS int) *
> verifyArray[digit] );
> END LOOP;
>
> -- CALCULATE THE VERIFICATION NUMBER
> verificationNumber = 11 - (auxValue % 11);
>
> -- REPLACE THE TWO DIGITS VERIFICATION NUMBER
> IF( verificationNumber = 11 ) THEN
> RETURN 0;
> ELSEIF ( verificationNumber = 10 ) THEN
> RETURN 9;
> ELSE
> RETURN verificationNumber;
> END IF;
>
> END IF;
>
> END;
> $$ LANGUAGE plpgsql;
>
> -- ----------------------------
> -- INSERTs to probe the functions
> -- ----------------------------
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 1');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 2');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 3');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 4');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 5');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 6');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 7');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 8');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 9');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 10');
>
>
> It is my first post so sorry about the format of the SQL Dump and
> sorry about my english.
> Note: there is a second function that calculate a verification
> number like an argentinian code called CUIL (only available for 10
> digits numbers)
> Regards....
>
> Nahuel Alejandro Ramos.
>
You didn't like UUID?
Yes. I looked this solution but it is not a "only numbers" ID. I would like a random unique "number" Id. For example: generate a credit number randomly (like the example I post).
I used to insert an MD5 field but this time I need "only numbers" Id.
Regards...
Nahuel Alejandro Ramos.
I used to insert an MD5 field but this time I need "only numbers" Id.
Regards...
Nahuel Alejandro Ramos.
On Tue, Oct 20, 2009 at 4:53 PM, Rob Sargent <robjsargent@gmail.com> wrote:
You didn't like UUID?
Nahuel Alejandro Ramos wrote:
> Hi all,
> I was searching for a sequence (for serials) that let me use a random
> unique number ID on a Primary Key or a simple index.
> I have not found a solution so I have done it by myself. I would like
> to share it so here it is:
>
> -- ----------------------------
> -- Create language "plpgsql"
> -- ----------------------------
> CREATE LANGUAGE plpgsql;
>
> -- ----------------------------
> -- Table structure for "public"."tarjeta"
> -- ----------------------------
> drop table "public"."tarjeta";
> CREATE TABLE "public"."tarjeta"(
> "idtarjeta" int8 NOT NULL DEFAULT randomuniqueidtarjeta(),
> "fechaemision" timestamp NOT NULL DEFAULT now(),
> "descripcion" varchar(255) ,
> PRIMARY KEY ("idtarjeta")
> ) WITHOUT OIDS;
>
> -- ----------------------------
> -- Definition of function "randomuniqueidtarjeta"
> -- ----------------------------
>
> CREATE OR REPLACE FUNCTION randomUniqueIdTarjeta() RETURNS bigint AS $$
>
> DECLARE
>
> -- SET THE KEY SIZE (IN CHARACTERS)
> idSize constant integer := 10;
>
> sizeMultiplicator constant bigint := 10 ^ idSize;
>
> loopLimit bigint := sizeMultiplicator * 4;
> randomNumber bigint;
> canIUseIt boolean := false;
>
> BEGIN
>
> -- LOOP UNTIL FIND AN UNIQUE RANDOM NUMBER OR FILL THE LOOP LIMIT
> WHILE ( not ( canIUseIt ) and ( loopLimit > 0) ) LOOP
>
> -- CALCULATE A TEN DIGITS RANDOM NUMBER
> randomNumber := CAST ( ( random() * sizeMultiplicator ) AS bigint );
>
> -- VALIDATE THAT THE NUMBER WON'T START WITH 0
> IF ( (randomNumber >= sizeMultiplicator / 10 ) and (
> randomNumber < sizeMultiplicator ) ) THEN
>
> -- CHECK THAN RANDOM NUMBER NOT EXISTS ON TABLE
> -- IMPORTANT!!! CHANGE WITH TABLE AND FIELD TO SEARCH FOR A
> DUPLICATATION
> PERFORM idtarjeta FROM tarjeta WHERE idtarjeta = randomNumber;
> IF NOT FOUND THEN
> canIUseIt = true;
> END IF;
>
> END IF;
>
> loopLimit = loopLimit - 1;
>
> END LOOP;
>
> -- IF LOOP ENDS WITH A UNIQUE RANDOM NUMBER RETURNS THE NUMBER
> CONCATENATED WITH A VERIFICATION NUMBER ELSE RAISE AN EXCEPTION
> IF ( canIUseIt ) THEN
> RETURN CAST ( ( CAST ( randomNumber AS text ) || CAST (
> verificationNumber( CAST (randomNumber AS text ) ) AS text ) ) AS
> bigint ) ;
> ELSE
> RAISE EXCEPTION 'Could not calculate a Random Unique ID on table
> Tarjeta.';
> END IF;
>
> END;
> $$ LANGUAGE plpgsql;
>
> -- ----------------------------
> -- Definition of function "randomuniqueidtarjeta"
> -- ----------------------------
>
> CREATE OR REPLACE FUNCTION verificationNumber(id text) RETURNS integer AS $$
> DECLARE
>
> auxValue integer := 0;
> verifyArray constant integer[] :=ARRAY [5,4,3,2,7,6,5,4,3,2,1];
> verificationNumber integer := 0;
>
> BEGIN
>
> -- ASK FOR ID LENGTH EQUAL TO 10 DIGITS. THE ALGORITHM WORKS ONLY FOR
> IF ( LENGTH( id ) <> 10 ) THEN
>
> RAISE EXCEPTION 'Could not calculate a verification number. The
> ID must have 10 digits.';
>
> ELSE
>
> -- LOOP ON THE TEN DIGITS AND MULTIPLY WITH THE SAME POSITION ON
> virifyArray
> FOR digit IN 1..10 LOOP
> auxValue = auxValue + ( CAST(SUBSTR(id, digit, 1) AS int) *
> verifyArray[digit] );
> END LOOP;
>
> -- CALCULATE THE VERIFICATION NUMBER
> verificationNumber = 11 - (auxValue % 11);
>
> -- REPLACE THE TWO DIGITS VERIFICATION NUMBER
> IF( verificationNumber = 11 ) THEN
> RETURN 0;
> ELSEIF ( verificationNumber = 10 ) THEN
> RETURN 9;
> ELSE
> RETURN verificationNumber;
> END IF;
>
> END IF;
>
> END;
> $$ LANGUAGE plpgsql;
>
> -- ----------------------------
> -- INSERTs to probe the functions
> -- ----------------------------
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 1');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 2');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 3');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 4');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 5');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 6');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 7');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 8');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 9');
> INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 10');
>
>
> It is my first post so sorry about the format of the SQL Dump and
> sorry about my english.
> Note: there is a second function that calculate a verification
> number like an argentinian code called CUIL (only available for 10
> digits numbers)
> Regards....
>
> Nahuel Alejandro Ramos.
>
Suit yourself, of course, but the numbers on my credit cards are far,
far from random :)
Nahuel Alejandro Ramos wrote:
> Yes. I looked this solution but it is not a "only numbers" ID. I would
> like a random unique "number" Id. For example: generate a credit number
> randomly (like the example I post).
> I used to insert an MD5 field but this time I need "only numbers" Id.
> Regards...
>
> Nahuel Alejandro Ramos.
>
>
> On Tue, Oct 20, 2009 at 4:53 PM, Rob Sargent <robjsargent@gmail.com
> <mailto:robjsargent@gmail.com>> wrote:
>
>
>
> Nahuel Alejandro Ramos wrote:
> > Hi all,
> > I was searching for a sequence (for serials) that let me use a
> random
> > unique number ID on a Primary Key or a simple index.
> > I have not found a solution so I have done it by myself. I would
> like
> > to share it so here it is:
> >
> > -- ----------------------------
> > -- Create language "plpgsql"
> > -- ----------------------------
> > CREATE LANGUAGE plpgsql;
> >
> > -- ----------------------------
> > -- Table structure for "public"."tarjeta"
> > -- ----------------------------
> > drop table "public"."tarjeta";
> > CREATE TABLE "public"."tarjeta"(
> > "idtarjeta" int8 NOT NULL DEFAULT randomuniqueidtarjeta(),
> > "fechaemision" timestamp NOT NULL DEFAULT now(),
> > "descripcion" varchar(255) ,
> > PRIMARY KEY ("idtarjeta")
> > ) WITHOUT OIDS;
> >
> > -- ----------------------------
> > -- Definition of function "randomuniqueidtarjeta"
> > -- ----------------------------
> >
> > CREATE OR REPLACE FUNCTION randomUniqueIdTarjeta() RETURNS bigint
> AS $$
> >
> > DECLARE
> >
> > -- SET THE KEY SIZE (IN CHARACTERS)
> > idSize constant integer := 10;
> >
> > sizeMultiplicator constant bigint := 10 ^ idSize;
> >
> > loopLimit bigint := sizeMultiplicator * 4;
> > randomNumber bigint;
> > canIUseIt boolean := false;
> >
> > BEGIN
> >
> > -- LOOP UNTIL FIND AN UNIQUE RANDOM NUMBER OR FILL THE LOOP LIMIT
> > WHILE ( not ( canIUseIt ) and ( loopLimit > 0) ) LOOP
> >
> > -- CALCULATE A TEN DIGITS RANDOM NUMBER
> > randomNumber := CAST ( ( random() * sizeMultiplicator ) AS
> bigint );
> >
> > -- VALIDATE THAT THE NUMBER WON'T START WITH 0
> > IF ( (randomNumber >= sizeMultiplicator / 10 ) and (
> > randomNumber < sizeMultiplicator ) ) THEN
> >
> > -- CHECK THAN RANDOM NUMBER NOT EXISTS ON TABLE
> > -- IMPORTANT!!! CHANGE WITH TABLE AND FIELD TO SEARCH
> FOR A
> > DUPLICATATION
> > PERFORM idtarjeta FROM tarjeta WHERE idtarjeta =
> randomNumber;
> > IF NOT FOUND THEN
> > canIUseIt = true;
> > END IF;
> >
> > END IF;
> >
> > loopLimit = loopLimit - 1;
> >
> > END LOOP;
> >
> > -- IF LOOP ENDS WITH A UNIQUE RANDOM NUMBER RETURNS THE NUMBER
> > CONCATENATED WITH A VERIFICATION NUMBER ELSE RAISE AN EXCEPTION
> > IF ( canIUseIt ) THEN
> > RETURN CAST ( ( CAST ( randomNumber AS text ) || CAST (
> > verificationNumber( CAST (randomNumber AS text ) ) AS text ) ) AS
> > bigint ) ;
> > ELSE
> > RAISE EXCEPTION 'Could not calculate a Random Unique ID on
> table
> > Tarjeta.';
> > END IF;
> >
> > END;
> > $$ LANGUAGE plpgsql;
> >
> > -- ----------------------------
> > -- Definition of function "randomuniqueidtarjeta"
> > -- ----------------------------
> >
> > CREATE OR REPLACE FUNCTION verificationNumber(id text) RETURNS
> integer AS $$
> > DECLARE
> >
> > auxValue integer := 0;
> > verifyArray constant integer[] :=ARRAY [5,4,3,2,7,6,5,4,3,2,1];
> > verificationNumber integer := 0;
> >
> > BEGIN
> >
> > -- ASK FOR ID LENGTH EQUAL TO 10 DIGITS. THE ALGORITHM WORKS
> ONLY FOR
> > IF ( LENGTH( id ) <> 10 ) THEN
> >
> > RAISE EXCEPTION 'Could not calculate a verification
> number. The
> > ID must have 10 digits.';
> >
> > ELSE
> >
> > -- LOOP ON THE TEN DIGITS AND MULTIPLY WITH THE SAME
> POSITION ON
> > virifyArray
> > FOR digit IN 1..10 LOOP
> > auxValue = auxValue + ( CAST(SUBSTR(id, digit, 1) AS
> int) *
> > verifyArray[digit] );
> > END LOOP;
> >
> > -- CALCULATE THE VERIFICATION NUMBER
> > verificationNumber = 11 - (auxValue % 11);
> >
> > -- REPLACE THE TWO DIGITS VERIFICATION NUMBER
> > IF( verificationNumber = 11 ) THEN
> > RETURN 0;
> > ELSEIF ( verificationNumber = 10 ) THEN
> > RETURN 9;
> > ELSE
> > RETURN verificationNumber;
> > END IF;
> >
> > END IF;
> >
> > END;
> > $$ LANGUAGE plpgsql;
> >
> > -- ----------------------------
> > -- INSERTs to probe the functions
> > -- ----------------------------
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 1');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 2');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 3');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 4');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 5');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 6');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 7');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 8');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 9');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 10');
> >
> >
> > It is my first post so sorry about the format of the SQL
> Dump and
> > sorry about my english.
> > Note: there is a second function that calculate a verification
> > number like an argentinian code called CUIL (only available for 10
> > digits numbers)
> > Regards....
> >
> > Nahuel Alejandro Ramos.
> >
>
> You didn't like UUID?
>
>
:D, Yeah, i know. Its only an example. We are using this algorithm to give a random unique Id to our clients. The need was to give a PK absolute independent of time. Thanks to Ivan, for the pseudo-random posted, I am looking it.
Regards...
Nahuel Alejandro Ramos.
Regards...
Nahuel Alejandro Ramos.
On Tue, Oct 20, 2009 at 5:03 PM, Rob Sargent <robjsargent@gmail.com> wrote:
Suit yourself, of course, but the numbers on my credit cards are far,
far from random :)
Nahuel Alejandro Ramos wrote:
> Yes. I looked this solution but it is not a "only numbers" ID. I would
> like a random unique "number" Id. For example: generate a credit number
> randomly (like the example I post).
> I used to insert an MD5 field but this time I need "only numbers" Id.
> Regards...
>
> Nahuel Alejandro Ramos.
>
>
> On Tue, Oct 20, 2009 at 4:53 PM, Rob Sargent <robjsargent@gmail.com> <mailto:robjsargent@gmail.com>> wrote:
>
>
>
> Nahuel Alejandro Ramos wrote:
> > Hi all,
> > I was searching for a sequence (for serials) that let me use a
> random
> > unique number ID on a Primary Key or a simple index.
> > I have not found a solution so I have done it by myself. I would
> like
> > to share it so here it is:
> >
> > -- ----------------------------
> > -- Create language "plpgsql"
> > -- ----------------------------
> > CREATE LANGUAGE plpgsql;
> >
> > -- ----------------------------
> > -- Table structure for "public"."tarjeta"
> > -- ----------------------------
> > drop table "public"."tarjeta";
> > CREATE TABLE "public"."tarjeta"(
> > "idtarjeta" int8 NOT NULL DEFAULT randomuniqueidtarjeta(),
> > "fechaemision" timestamp NOT NULL DEFAULT now(),
> > "descripcion" varchar(255) ,
> > PRIMARY KEY ("idtarjeta")
> > ) WITHOUT OIDS;
> >
> > -- ----------------------------
> > -- Definition of function "randomuniqueidtarjeta"
> > -- ----------------------------
> >
> > CREATE OR REPLACE FUNCTION randomUniqueIdTarjeta() RETURNS bigint
> AS $$
> >
> > DECLARE
> >
> > -- SET THE KEY SIZE (IN CHARACTERS)
> > idSize constant integer := 10;
> >
> > sizeMultiplicator constant bigint := 10 ^ idSize;
> >
> > loopLimit bigint := sizeMultiplicator * 4;
> > randomNumber bigint;
> > canIUseIt boolean := false;
> >
> > BEGIN
> >
> > -- LOOP UNTIL FIND AN UNIQUE RANDOM NUMBER OR FILL THE LOOP LIMIT
> > WHILE ( not ( canIUseIt ) and ( loopLimit > 0) ) LOOP
> >
> > -- CALCULATE A TEN DIGITS RANDOM NUMBER
> > randomNumber := CAST ( ( random() * sizeMultiplicator ) AS
> bigint );
> >
> > -- VALIDATE THAT THE NUMBER WON'T START WITH 0
> > IF ( (randomNumber >= sizeMultiplicator / 10 ) and (
> > randomNumber < sizeMultiplicator ) ) THEN
> >
> > -- CHECK THAN RANDOM NUMBER NOT EXISTS ON TABLE
> > -- IMPORTANT!!! CHANGE WITH TABLE AND FIELD TO SEARCH
> FOR A
> > DUPLICATATION
> > PERFORM idtarjeta FROM tarjeta WHERE idtarjeta =
> randomNumber;
> > IF NOT FOUND THEN
> > canIUseIt = true;
> > END IF;
> >
> > END IF;
> >
> > loopLimit = loopLimit - 1;
> >
> > END LOOP;
> >
> > -- IF LOOP ENDS WITH A UNIQUE RANDOM NUMBER RETURNS THE NUMBER
> > CONCATENATED WITH A VERIFICATION NUMBER ELSE RAISE AN EXCEPTION
> > IF ( canIUseIt ) THEN
> > RETURN CAST ( ( CAST ( randomNumber AS text ) || CAST (
> > verificationNumber( CAST (randomNumber AS text ) ) AS text ) ) AS
> > bigint ) ;
> > ELSE
> > RAISE EXCEPTION 'Could not calculate a Random Unique ID on
> table
> > Tarjeta.';
> > END IF;
> >
> > END;
> > $$ LANGUAGE plpgsql;
> >
> > -- ----------------------------
> > -- Definition of function "randomuniqueidtarjeta"
> > -- ----------------------------
> >
> > CREATE OR REPLACE FUNCTION verificationNumber(id text) RETURNS
> integer AS $$
> > DECLARE
> >
> > auxValue integer := 0;
> > verifyArray constant integer[] :=ARRAY [5,4,3,2,7,6,5,4,3,2,1];
> > verificationNumber integer := 0;
> >
> > BEGIN
> >
> > -- ASK FOR ID LENGTH EQUAL TO 10 DIGITS. THE ALGORITHM WORKS
> ONLY FOR
> > IF ( LENGTH( id ) <> 10 ) THEN
> >
> > RAISE EXCEPTION 'Could not calculate a verification
> number. The
> > ID must have 10 digits.';
> >
> > ELSE
> >
> > -- LOOP ON THE TEN DIGITS AND MULTIPLY WITH THE SAME
> POSITION ON
> > virifyArray
> > FOR digit IN 1..10 LOOP
> > auxValue = auxValue + ( CAST(SUBSTR(id, digit, 1) AS
> int) *
> > verifyArray[digit] );
> > END LOOP;
> >
> > -- CALCULATE THE VERIFICATION NUMBER
> > verificationNumber = 11 - (auxValue % 11);
> >
> > -- REPLACE THE TWO DIGITS VERIFICATION NUMBER
> > IF( verificationNumber = 11 ) THEN
> > RETURN 0;
> > ELSEIF ( verificationNumber = 10 ) THEN
> > RETURN 9;
> > ELSE
> > RETURN verificationNumber;
> > END IF;
> >
> > END IF;
> >
> > END;
> > $$ LANGUAGE plpgsql;
> >
> > -- ----------------------------
> > -- INSERTs to probe the functions
> > -- ----------------------------
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 1');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 2');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 3');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 4');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 5');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 6');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 7');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 8');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 9');
> > INSERT INTO tarjeta (descripcion) VALUES ('Tarjeta 10');
> >
> >
> > It is my first post so sorry about the format of the SQL
> Dump and
> > sorry about my english.
> > Note: there is a second function that calculate a verification
> > number like an argentinian code called CUIL (only available for 10
> > digits numbers)
> > Regards....
> >
> > Nahuel Alejandro Ramos.
> >
>
> You didn't like UUID?
>
>
On Tue, 20 Oct 2009 16:49:17 -0300 Nahuel Alejandro Ramos <nahuelon@gmail.com> wrote: > Hi all, > I was searching for a sequence (for serials) that let me use a > random unique number ID on a Primary Key or a simple index. > I have not found a solution so I have done it by myself. I would > like to share it so here it is: http://www.webthatworks.it/d1/node/page/pseudo_random_sequences_postgresql Adapted from Daniel Verite suggestion. -- Ivan Sergio Borgonovo http://www.webthatworks.it
Nahuel Alejandro Ramos wrote: > Hi all, > I was searching for a sequence (for serials) that let me use a random > unique number ID on a Primary Key or a simple index. > I have not found a solution so I have done it by myself. I would like to > share it so here it is: Here's what I'm using: http://wiki.postgresql.org/wiki/Pseudo_encrypt thanks to the incredibly helpful folks on this list, in this case particularly Daniel Verite. -- Craig Ringer