I am use Firebird 2.5
I have multiple tables with column name 'col1', and I would like delete it.
I can use this statement:
DELETE FROM RDB$RELATION_FIELDS
WHERE RDB$FIELD_NAME = 'col1';
But I do not know is it safe.
I try to use execute block for multiple execute statements, but I do not know, how to combine it.
SET TERM ^ ;
EXECUTE BLOCK AS
DECLARE s AS VARCHAR(200)
BEGIN
WHILE (SELECT rf.RDB$RELATION_NAME FROM RDB$RELATION_FIELDS rf WHERE rf.RDB$FIELD_NAME = 'AKTYWNY';) DO
BEGIN
ALTER TABLE :s DROP c1;
END
END^
SET TERM ; ^
This is example how to do this in stored procedure :
create or alter procedure DELETE_COL (
F_COL char(31))
as
declare variable V_STAT varchar(256);
declare variable R_NAME char(31);
begin
for
select f.rdb$relation_name
from rdb$relation_fields f
join rdb$relations r on f.rdb$relation_name = r.rdb$relation_name
and r.rdb$view_blr is null
and (r.rdb$system_flag is null or r.rdb$system_flag = 0)
where f.rdb$field_name = :f_col
order by 1, f.rdb$field_position
into
:r_name -- Table Name
do
begin
v_stat = 'alter table ' || :r_name || ' drop ' || :f_col;
execute statement(v_stat); /*because alter table ... is not allowed here */
end
end
You can use this in execute block also.
Related
I am getting the following error while creating a stored procedure for testing purpose:
SQL Error [42601]: An unexpected token "DECLARE GLOBAL TEMPORARY TABLE
SESSION" was found following "RSOR WITH RETURN FOR". Expected tokens may include: "".. SQLCODE=-104, SQLSTATE=42601, DRIVER=4.21.29
Code:
CREATE OR REPLACE PROCEDURE Test ( IN GE_OutPutType SMALLINT)
----------------------------------------------------------------------------------------------------
DYNAMIC RESULT SETS 1 LANGUAGE SQL
BEGIN
DECLARE C CURSOR WITH RETURN FOR DECLARE GLOBAL TEMPORARY TABLE
SESSION.TEMP (DATE CHAR(10) NOT NULL,
SALARY DECIMAL(9,
2) ,
COMM DECIMAL(9,
2));
INSERT
INTO
SESSION.TEMP (DATE,
SALARY,
COMM) SELECT
VARCHAR_FORMAT(CURRENT_DATE,
'MM/DD/YYYY'),
10.2,
11.5
FROM
sysibm.sysdummy1
IF GE_OutPutType = 1
BEGIN
SELECT
*
FROM
TEMP
ELSEIF GE_OutPutType = 2 SELECT
'HEADER' CONCAT SPACE(1979) CONCAT 'H'
FROM
sysibm.sysdummy1
END OPEN C;
END
Your syntax is not valid.
You must declare your temporary table independently of your cursor.
You cannot combine these in a single statement.
Use dynamic-SQL features to achieve what you need.
Use instead the format:
Declare c1 cursor with return to caller for Statement1
and
set v_cursor_text = 'select ... from session.temp ; `
then use
prepare Statement1 from v_cursor_text;
and before you exit the stored procedure you need to leave the cursor opened:
open c1;
Do study the Db2 online documentation to learn more about these features.
Here is a small fragment of your procedure showing what I mean:
CREATE OR REPLACE PROCEDURE mytest ( IN GE_OutPutType SMALLINT)
DYNAMIC RESULT SETS 1
LANGUAGE SQL
specific mytest
BEGIN
DECLARE v_cursor_text varchar(1024);
DECLARE C1 CURSOR WITH RETURN FOR Statement1;
DECLARE GLOBAL TEMPORARY TABLE SESSION.TEMP (
DATE CHAR(10) NOT NULL,
SALARY DECIMAL(9,
2) ,
COMM DECIMAL(9,
2))
with replace on commit preserve rows not logged;
INSERT INTO SESSION.TEMP (DATE, SALARY, COMM)
SELECT VARCHAR_FORMAT(CURRENT_DATE, 'MM/DD/YYYY'),
10.2,
11.5
FROM sysibm.sysdummy1 ;
if GE_OutPutType = 1
then
set v_cursor_text = 'select * from session.temp';
end if;
if GE_OutPutType = 2
then
set v_cursor_text = 'select ''header'' concat space(1979) concat ''H'' from sysibm.sysdummy1';
end if;
prepare Statement1 from v_cursor_text;
open c1;
END#
I have a few db tables.
I want write universtal postgres function on copy rows to history tables
I have tables:
table1
table1_h
table2
table2_h
I wrote function (with help stackoverflow)
CREATE OR REPLACE FUNCTION copy_history_f() RETURNS TRIGGER AS
$BODY$
DECLARE
tablename_h text:= TG_TABLE_NAME || '_h';
BEGIN
EXECUTE 'INSERT INTO ' || quote_ident(TG_TABLE_SCHEMA) || '.' || quote_ident(tablename_h) || ' VALUES (' || OLD.* ||')';
RETURN NULL;
END;
$BODY$
LANGUAGE plpgsql VOLATILE;
And functions was create, but after update is error.
ERROR: syntax error at or near ","
ROW 1: ...RT INTO table1_h VALUES ((12,,,0,,"Anto...
I know where is error in this insert but I don't know how I repair that.
Structure tables table1 and table1_h are identical but table1_h has one more column (id_h)
Can you help me, how I have create psql function?
Thnak you.
drop table if exists t;
drop table if exists t_h;
drop function if exists ftg();
create table t(i serial, x numeric);
insert into t(x) values(1.1),(2.2);
create table t_h(i int, x numeric);
create function ftg() returns trigger language plpgsql as $ftg$
declare
tablename_h text:= TG_TABLE_NAME || '_h';
begin
execute format($q$ insert into %I.%I select $1.*; $q$, TG_TABLE_SCHEMA, tablename_h) using old;
return null;
end $ftg$;
create trigger tg_t after delete on t for each row execute procedure ftg();
delete from t where i = 1;
select * from t_h;
dbfiddle
Update It solves your problem, but I think that you want to have a bit more info in your history tables. It will be more complex a bit:
drop table if exists t;
drop table if exists t_h;
drop function if exists ftg();
create table t(i serial, x numeric);
insert into t(x) values(1.1),(2.2);
create table t_h(
hi serial, -- just ID
hd timestamp, -- timestamp
hu text, -- user who made changes
ha text, -- action
i int, x numeric
);
create function ftg() returns trigger language plpgsql as $ftg$
declare
tablename_h text:= TG_TABLE_NAME || '_h';
begin
execute format(
$q$
insert into %I.%I
select
nextval(%L || '_hi_seq'),
clock_timestamp(),
current_user,
%L,
$1.*
$q$, TG_TABLE_SCHEMA, tablename_h, tablename_h, TG_OP) using old;
return null;
end $ftg$;
create trigger tg_t after delete or update on t for each row execute procedure ftg();
update t set x = x * 2;
update t set x = x * 2 where i = 2;
delete from t where i = 1;
select * from t_h;
dbfiddle
I assume you are inserting the 'old' values from table1 into table1_h.
The additional column is your problem. When you using an insert without naming columns you must use a matching number and type for the insert.
You must use column referencing.
eg.
Insert into table1_h(column1, column2, column3)
values (a,b,c)
Consider a default value for the additional column in table table1_h.
I have a parent table layer_1_ and a number of child tables layer_1_points, layer_1_linestrings etc. which contain some geometry data. Each child table has its own geometry constraint. So, for example, layer_1_points has this constraint:
CONSTRAINT enforce_geotype_geom_geom CHECK (geometrytype(geom) = 'POINT'::text)
Whereas layer_1_linestrings table has this constraint:
CONSTRAINT enforce_geotype_geom_geom CHECK (geometrytype(geom) = 'LINESTRING'::text)
Many other layer tables have similar names: layer_2_, layer_3_, ..., layer_N_. And all of them have their own child tables. What I want to achive is that when a user inserts to a parent table (layer_N_), then this insert statement should be forwarded to a particular child table (layer_N_points etc.). So, for example, when I do:
INSERT INTO layer_1_ (geom) VALUES(ST_GeomFromText('POINT(0 0)', 3857))
I should actually insert to layer_1_points, because geom type is POINT. To achive all this I created this trigger function and the trigger itself:
CREATE OR REPLACE FUNCTION trigger_layer_insert()
RETURNS trigger AS
$$
DECLARE
var_geomtype text;
table_name text;
layer_id text := (TG_ARGV[0])::text;
BEGIN
var_geomtype := geometrytype(NEW.geom);
IF var_geomtype = 'POINT' THEN
table_name := (SELECT concat ('layer_', layer_id, '_points'));
ELSIF var_geomtype = 'MULTIPOINT' THEN
table_name := (SELECT concat ('layer_', layer_id, '_multipoints'));
ELSIF var_geomtype = 'LINESTRING' THEN
table_name := (SELECT concat ('layer_', layer_id, '_linestrings'));
ELSIF var_geomtype = 'MULTILINESTRING' THEN
table_name := (SELECT concat ('layer_', layer_id, '_multilinestrings'));
ELSIF var_geomtype = 'POLYGON' THEN
table_name := (SELECT concat ('layer_', layer_id, '_polygons'));
ELSIF var_geomtype = 'MULTIPOLYGON' THEN
table_name := (SELECT concat ('layer_', layer_id, '_multipolygons'));
END IF;
EXECUTE '
INSERT INTO ' || table_name || '
SELECT * FROM (SELECT NEW.*) AS t
';
RETURN NULL;
END;
$$
LANGUAGE 'plpgsql' VOLATILE;
CREATE TRIGGER trigger_layer_1_ BEFORE INSERT
ON layer_1_ FOR EACH ROW
EXECUTE PROCEDURE trigger_layer_insert(1);
However, when I do actual insert like:
INSERT INTO layer_1_ (geom) VALUES(ST_GeomFromText('POINT(0 0)', 3857))
I get an error message:
ERROR: missing FROM-clause entry for table "new"
LINE 3: SELECT * FROM (SELECT NEW.*) AS t
^
QUERY:
INSERT INTO layer_1_points
SELECT * FROM (SELECT NEW.*) AS t
So, what is wrong with SELECT NEW.* and how can I fix it? Thanks!
EDIT
I also tried this:
EXECUTE '
INSERT INTO ' || table_name || '
SELECT * FROM (SELECT NEW.*) AS t
' USING NEW;
But it has no effect.
When you execute something using PLPGSQL statement EXECUTE it runs in the different context so local variables is not visible there. To pass variable(s) the EXECUTE '<SQL script>' USING <variables list>; form is used:
EXECUTE 'insert into table(field1, field2) values ($1, $2)' USING var1, var2;
So the statement should be:
EXECUTE 'INSERT INTO ' || table_name || ' SELECT * FROM SELECT $1.*) AS t'
USING NEW;
But much more secure is using format function:
execute format('INSERT INTO %I SELECT * FROM SELECT $1.*) AS t', table_name)
I'm attempting to write an area of a function in PL/pgSQL that loops through an hstore and sets a record's column(the key of the hstore) to a specific value (the value of the hstore). I'm using Postgres 9.1.
The hstore will look like: ' "column1"=>"value1","column2"=>"value2" '
Generally, here is what I want from a function that takes in an hstore and has a record with values to modify:
FOR my_key, my_value IN
SELECT key,
value
FROM EACH( in_hstore )
LOOP
EXECUTE 'SELECT $1'
INTO my_row.my_key
USING my_value;
END LOOP;
The error which I am getting with this code:
"myrow" has no field "my_key". I've been searching for quite a while now for a solution, but everything else I've tried to achieve the same result hasn't worked.
Simpler alternative to your posted answer. Should perform much better.
This function retrieves a row from a given table (in_table_name) and primary key value (in_row_pk), and inserts it as new row into the same table, with some values replaced (in_override_values). The new primary key value as per default is returned (pk_new).
CREATE OR REPLACE FUNCTION f_clone_row(in_table_name regclass
, in_row_pk int
, in_override_values hstore
, OUT pk_new int)
LANGUAGE plpgsql AS
$func$
DECLARE
_pk text; -- name of PK column
_cols text; -- list of names of other columns
BEGIN
-- Get name of PK column
SELECT INTO _pk a.attname
FROM pg_catalog.pg_index i
JOIN pg_catalog.pg_attribute a ON a.attrelid = i.indrelid
AND a.attnum = i.indkey[0] -- single PK col!
WHERE i.indrelid = in_table_name
AND i.indisprimary;
-- Get list of columns excluding PK column
SELECT INTO _cols string_agg(quote_ident(attname), ',')
FROM pg_catalog.pg_attribute
WHERE attrelid = in_table_name -- regclass used as OID
AND attnum > 0 -- exclude system columns
AND attisdropped = FALSE -- exclude dropped columns
AND attname <> _pk; -- exclude PK column
-- INSERT cloned row with override values, returning new PK
EXECUTE format('
INSERT INTO %1$I (%2$s)
SELECT %2$s
FROM (SELECT (t #= $1).* FROM %1$I t WHERE %3$I = $2) x
RETURNING %3$I'
, in_table_name, _cols, _pk)
USING in_override_values, in_row_pk -- use override values directly
INTO pk_new; -- return new pk directly
END
$func$;
Call:
SELECT f_clone_row('tbl', 1, '"col1"=>"foo_new","col2"=>"bar_new"');
db<>fiddle here
Old sqlfiddle
Use regclass as input parameter type, so only valid table names can be used to begin with and SQL injection is ruled out. The function also fails earlier and more gracefully if you should provide an illegal table name.
Use an OUT parameter (pk_new) to simplify the syntax.
No need to figure out the next value for the primary key manually. It is inserted automatically and returned after the fact. That's not only simpler and faster, you also avoid wasted or out-of-order sequence numbers.
Use format() to simplify the assembly of the dynamic query string and make it less error-prone. Note how I use positional parameters for identifiers and unquoted strings respectively.
I build on your implicit assumption that allowed tables have a single primary key column of type integer with a column default. Typically serial columns.
Key element of the function is the final INSERT:
Merge override values with the existing row using the #= operator in a subselect and decompose the resulting row immediately.
Then you can select only relevant columns in the main SELECT.
Let Postgres assign the default value for the PK and get it back with the RETURNING clause.
Write the returned value into the OUT parameter directly.
All done in a single SQL command, that is generally fastest.
Since I didn't want to have to use any external functions for speed purposes, I created a solution using hstores to insert a record into a table:
CREATE OR REPLACE FUNCTION fn_clone_row(in_table_name character varying, in_row_pk integer, in_override_values hstore)
RETURNS integer
LANGUAGE plpgsql
AS $function$
DECLARE
my_table_pk_col_name varchar;
my_key text;
my_value text;
my_row record;
my_pk_default text;
my_pk_new integer;
my_pk_new_text text;
my_row_hstore hstore;
my_row_keys text[];
my_row_keys_list text;
my_row_values text[];
my_row_values_list text;
BEGIN
-- Get the next value of the pk column for the table.
SELECT ad.adsrc,
at.attname
INTO my_pk_default,
my_table_pk_col_name
FROM pg_attrdef ad
JOIN pg_attribute at
ON at.attnum = ad.adnum
AND at.attrelid = ad.adrelid
JOIN pg_class c
ON c.oid = at.attrelid
JOIN pg_constraint cn
ON cn.conrelid = c.oid
AND cn.contype = 'p'
AND cn.conkey[1] = at.attnum
JOIN pg_namespace n
ON n.oid = c.relnamespace
WHERE c.relname = in_table_name
AND n.nspname = 'public';
-- Get the next value of the pk in a local variable
EXECUTE ' SELECT ' || my_pk_default
INTO my_pk_new;
-- Set the integer value back to text for the hstore
my_pk_new_text := my_pk_new::text;
-- Add the next value statement to the hstore of changes to make.
in_override_values := in_override_values || hstore( my_table_pk_col_name, my_pk_new_text );
-- Copy over only the given row to the record.
EXECUTE ' SELECT * '
' FROM ' || quote_ident( in_table_name ) ||
' WHERE ' || quote_ident( my_table_pk_col_name ) ||
' = ' || quote_nullable( in_row_pk )
INTO my_row;
-- Replace the values that need to be changed in the column name array
my_row := my_row #= in_override_values;
-- Create an hstore of my record
my_row_hstore := hstore( my_row );
-- Create a string of comma-delimited, quote-enclosed column names
my_row_keys := akeys( my_row_hstore );
SELECT array_to_string( array_agg( quote_ident( x.colname ) ), ',' )
INTO my_row_keys_list
FROM ( SELECT unnest( my_row_keys ) AS colname ) x;
-- Create a string of comma-delimited, quote-enclosed column values
my_row_values := avals( my_row_hstore );
SELECT array_to_string( array_agg( quote_nullable( x.value ) ), ',' )
INTO my_row_values_list
FROM ( SELECT unnest( my_row_values ) AS value ) x;
-- Insert the values into the columns of a new row
EXECUTE 'INSERT INTO ' || in_table_name || '(' || my_row_keys_list || ')'
' VALUES (' || my_row_values_list || ')';
RETURN my_pk_new;
END
$function$;
It's quite a bit longer than what I had envisioned, but it works and is actually quite speedy.
I'm trying to write a function in PL/PgSQL that have to work with a table it receives as a parameter.
I use EXECUTE..INTO..USING statements within the function definition to build dynamic queries (it's the only way I know to do this) but ... I encountered a problem with RECORD data types.
Let's consider the follow (extremely simplified) example.
-- A table with some values.
DROP TABLE IF EXISTS table1;
CREATE TABLE table1 (
code INT,
descr TEXT
);
INSERT INTO table1 VALUES ('1','a');
INSERT INTO table1 VALUES ('2','b');
-- The function code.
DROP FUNCTION IF EXISTS foo (TEXT);
CREATE FUNCTION foo (tbl_name TEXT) RETURNS VOID AS $$
DECLARE
r RECORD;
d TEXT;
BEGIN
FOR r IN
EXECUTE 'SELECT * FROM ' || tbl_name
LOOP
--SELECT r.descr INTO d; --IT WORK
EXECUTE 'SELECT ($1)' || '.descr' INTO d USING r; --IT DOES NOT WORK
RAISE NOTICE '%', d;
END LOOP;
END;
$$ LANGUAGE plpgsql STRICT;
-- Call foo function on table1
SELECT foo('table1');
It output the following error:
ERROR: could not identify column "descr" in record data type
although the syntax I used seems valid to me. I can't use the static select (commented in the example) because I want to dinamically refer the columns names.
So..someone know what's wrong with the above code?
It's true. You cannot to use type record outside PL/pgSQL space.
RECORD value is valid only in plpgsql.
you can do
EXECUTE 'SELECT $1.descr' INTO d USING r::text::xx;
$1 should be inside the || ,like || $1 || and give spaces properly then it will work.
BEGIN
EXECUTE ' delete from ' || quote_ident($1) || ' where condition ';
END;