For all tables in X, while X is
select table_name from all_tab_cols
where column_name = 'MY_COLUMN'
and owner='ADMIN'
I need to check, if the column MY_COLUMN has other values than 'Y' or 'N' and if it does, print out the table name.
Pseudo code:
for table in X:
if MY_COLUMN !='Y' or MY_COLUMN !='N':
print table
How to implement that in PL/SQL, with cursors I guess?
Following should work:
DECLARE
counter NUMBER;
cursor c1 is
select table_name from all_tab_cols
where column_name = 'MY_COLUMN'
and owner='ADMIN';
BEGIN
FOR rec IN c1 LOOP
DBMS_OUTPUT.PUT_LINE(rec.table_name);
EXECUTE IMMEDIATE 'select count(*) into :counter from '|| rec.table_name ||' where MY_COLUMN!= ''Y'' and MY_COLUMN!= ''N'' ';
if counter > 0 then
DBMS_OUTPUT.PUT_LINE(rec.table_name);
end if;
END LOOP;
END;
Basically we open a cursor with all tables containing that column, do a count for rows that have different values than Y or N, and if that count > 0, print the table.
The version of Wouter does not work for me.
Had to remove the semicolon (Oracle Database version 11.2.0.4.0 )
DECLARE
counter NUMBER;
BEGIN
select count(*) into counter from LASTID;
dbms_output.put_line(counter);
END;
/
Related
postgres 12
I am trying to loop through a table which has schema , table_names and columns
I want to do various things like finding nulls ,row count etc. I failed at the first hurdle trying to update the col records.
table i am using
CREATE TABLE test.table_study (
table_schema text,
table_name text,
column_name text,
records int,
No_Nulls int,
No_Blanks int,
per_pop int
);
I populate the table with some schema names ,tables and columns from information_schema.columns
insert into test.table_study select table_schema, table_name, column_name
from information_schema.columns
where table_schema like '%white'
order by table_schema, table_name, ordinal_position;
I want to populate the rest with a function
function :-
CREATE OR REPLACE PROCEDURE test.insert_data_population()
as $$
declare s record;
declare t record;
declare c record;
BEGIN
FOR s IN SELECT distinct table_schema FROM test.table_study
LOOP
FOR t IN SELECT distinct table_name FROM test.table_study where table_schema = s.table_schema
loop
FOR c IN SELECT column_name FROM test.table_study where table_name = t.table_name
LOOP
execute 'update test.table_study set records = (select count(*) from ' || s.table_schema || '.' || t.table_name || ') where table_study.table_name = '|| t.table_name ||';';
END LOOP;
END LOOP;
END LOOP;
END;
$$
LANGUAGE plpgsql;
I get this error SQL Error [42703]: ERROR: column "age" does not exist. the table age does exist.
when I take out the where clause
execute 'update referralunion.testinsert ti set records = (select count(*) from ' || s.table_schema || '.' || t.table_name || ') ;';
it works, I just cant figure out whats wrong?
Your procedure is structured entirely wrong. What it results in is an attempt to get every column name for every table name in every schema. I would guess results in your column does not exist error. Further is shows procedural thinking. SQL requires think in terms of sets. Below I use basically your query to demonstrate then a revised version which uses a single loop.
-- setup (dropping schema references)
create table table_study (
table_schema text,
table_name text,
column_name text,
records int,
no_nulls int,
no_blanks int,
per_pop int
);
insert into table_study(table_schema, table_name, column_name)
values ('s1','t1','age')
, ('s2','t1','xyz');
-- procedure replacing EXECUTE with Raise Notice.
create or replace procedure insert_data_population()
as $$
declare
s record;
t record;
c record;
line int = 0;
begin
for s in select distinct table_schema from table_study
loop
for t in select distinct table_name from table_study where table_schema = s.table_schema
loop
for c in select column_name from table_study where table_name = t.table_name
loop
line = line+1;
raise notice '%: update table_study set records = (select count(*) from %.% where table_study.table_name = %;'
, line, s.table_schema, t.table_name, c.column_name;
end loop;
end loop;
end loop;
end;
$$
language plpgsql;
Run procedure
do $$
begin
call insert_data_population();
end;
$$;
RESULTS
1: update table_study set records = (select count(*) from s2.t1 where table_study.table_name = age; 2: update table_study set records = (select count(*) from s2.t1 where table_study.table_name = xyz; 3: update table_study set records = (select count(*) from s1.t1 where table_study.table_name = age; 4: update table_study set records = (select count(*) from s1.t1 where table_study.table_name = xyz;
Notice lines 2 and 3. Each references a column name that does not exist in the table. This results from the FOR structure with the same table name in different schema.
Revision for Single Select statement with Single For loop.
create or replace
procedure insert_data_population()
language plpgsql
as $$
declare
s record;
line int = 0;
begin
for s in select distinct table_schema, table_name, column_name from table_study
loop
line = line+1;
raise notice '%: update table_study set records = (select count(*) from %.% where table_study.table_name = %;'
, line, s.table_schema, s.table_name, s.column_name;
end loop;
end;
$$;
do $$
begin
call insert_data_population();
end;
$$;
RESULTS
1: update table_study set records = (select count(*) from s2.t1 where table_study.table_name = xyz;
2: update table_study set records = (select count(*) from s1.t1 where table_study.table_name = age;
Note: In Postgres DECLARE begins a block. It is not necessary to declared each variable. I would actually consider it bad practice. In theory it could require an end for each declare as each could be considered a nested block. Fortunately Postgres does not require this.
I need to search in a large DB a table that matches with a column name, but this table must have more than 0 rows.
Here is the query by the way:
SELECT * FROM all_tab_columns WHERE column_name LIKE '%ID_SUPPORT%';
You could use single query to filter names and get actual number of rows:
SELECT owner, table_name, cnt
FROM all_tab_columns, XMLTABLE('/ROWSET/ROW' passing
(dbms_xmlgen.getxmltype(REPLACE(REPLACE(
'select COUNT(*) AS cnt from <owner>.<table_name>', '<owner>', owner)
, '<table_name>', table_name))) COLUMNS cnt INT)
WHERE column_name LIKE '%ID_SUPPORT%' AND cnt > 0;
DBFiddle Demo
Any chance this can be expanded/tweaked to yield the values of the first few rows for all tables?
Yes, by flattening row using JSON_ARRAYAGG(JSON_OBJECT(*)) Oracle 19c:
-- generic approach Oracle 19c
SELECT owner, table_name, cnt, example
FROM all_tab_columns, XMLTABLE('/ROWSET/ROW' passing
(dbms_xmlgen.getxmltype(REPLACE(REPLACE(
'select COUNT(*) AS cnt,
MAX((SELECT JSON_ARRAYAGG(JSON_OBJECT(*))
FROM <owner>.<table_name>
WHERE rownum < 10) -- taking up to 10 rows as example
) as example
from <owner>.<table_name>', '<owner>', owner)
, '<table_name>', table_name)))
COLUMNS cnt INT
, example VARCHAR2(1000))
WHERE column_name LIKE '%ID_SUPPORT%'
AND cnt > 0;
Demo contains hardcoded column list inside JSON_OBJECT. Oracle 19c and JSON_OBJECT(*) would allow any column list per table.
db<>fiddle demo
How it works:
find all tables that have column named '%ID_SUPPORT'
run query per table using dbms_xml_gen.getxmltype
in sub query count the rows, flatten few rows an example to JSON
return rows that have at least one record table
One way:
SELECT * FROM all_tables WHERE num_rows > 0
AND table_name in (SELECT table_name FROM all_tab_columns WHERE column_name LIKE '%ID_SUPPORT%')
If your DB is periodically analyzed the direct way is to use the following SQL :
SELECT *
FROM all_tables t
WHERE t.table_name LIKE '%ID_SUPPORT%'
and t.num_rows > 0;
More precise way to determine is using the following :
declare
v_val pls_integer := 0;
begin
for c in (
SELECT *
FROM all_tables t
WHERE t.table_name LIKE '%ID_SUPPORT%'
)
loop
execute immediate 'select count(1) from '||c.owner||'.'||c.table_name into v_val;
if v_val > 0 then
dbms_output.put_line('Table Name : '||c.table_name||' with '||v_val||' rows ');
end if;
end loop;
end;
I'm confused with the word matches. If you mean column, but not table, you may use the following routine to get the desired tables with columns whose names are like ID_SUPPORT :
declare
v_val pls_integer := 0;
begin
for c in (
SELECT t.*
FROM all_tab_columns c
JOIN all_tables t on ( c.table_name = t.table_name )
WHERE c.column_name LIKE '%ID_SUPPORT%'
)
loop
execute immediate 'select count(1) from '||c.owner||'.'||c.table_name into v_val;
if v_val > 0 then
dbms_output.put_line('Table Name : '||c.table_name||' with '||v_val||' rows ');
end if;
end loop;
end;
I need to verify converted data, distinct values and records counts. I would like to write statements so that I can enter a table name, then retrieve it's columns and use them in a query to get its distinct values (the actual values, not just a count of how many distinct) and their count.
I think I need to a CURSOR or CURSOR FOR LOOP and create something like this:
declare
cursor field_name
is
select COLUMN_NAME
from user_tab_cols
where table_name='TABLE1'
c_field_name field_name%ROWTYPE;
BEGIN
OPEN field_name
loop
fetch field_name INTO c_field_name;
exit when field_name%NOTFOUND;
end loop;
CLOSE field_name;
end;
Then run a query using that above in something like
select field_name, count(*)
from table1
group by field_name
Do I need to create 2 loop statements? I've not yet created one and can't quite get the context to get my results so far.
BEGIN
FOR myrow in (select field_name, count(*) as "count" from table1 group by field_name)
loop
dbms_output.put_line(myrow.field_name);
dbms_output.put_line(myrow.count);
end loop;
end;
Considering you will be giving the table name as parameter below code will print all the values of all the columns one by one along with the count of the values
create or replace PROCEDURE PR_PREP(
P_TABLE_NAME IN VARCHAR2)
IS
CURSOR CUR_COLUMNS (PA_TABLE_NAME VARCHAR2)
IS
SELECT COLUMN_NAME FROM ALL_TAB_COLUMNS WHERE TABLE_NAME = PA_TABLE_NAME;
COL_NAMES CUR_COLUMNS%ROWTYPE;
TYPE TYP_RECORD
IS
RECORD
(
FIELD_NAME VARCHAR2(255),
CNT INT);
TYPE TYP_OP_TABLE
IS
TABLE OF TYP_RECORD;
OP_TABLE TYP_OP_TABLE;
I INT;
V_SQL VARCHAR2(2000);
BEGIN
FOR COL_NAMES IN CUR_COLUMNS(P_TABLE_NAME)
LOOP
V_SQL := 'SELECT ' || COL_NAMES.COLUMN_NAME || ' AS FIELD_NAME ,
COUNT(*) AS CNT FROM ' ||
P_TABLE_NAME || ' GROUP BY ' || COL_NAMES.COLUMN_NAME ;
-- DBMS_OUTPUT.PUT_LINE (V_SQL);
EXECUTE IMMEDIATE V_SQL BULK COLLECT INTO OP_TABLE;
dbms_output.put_line('columna name = ' ||COL_NAMES.COLUMN_NAME);
FOR I IN OP_TABLE.FIRST .. OP_TABLE.LAST
LOOP
DBMS_OUTPUT.PUT_LINE('FIELD VALUE '||OP_TABLE(I).FIELD_NAME || ' COUNT = ' || OP_TABLE(I).CNT);
END LOOP;
DBMS_OUTPUT.PUT_LINE('ONE FILED ENDED , NEXT STARTED');
END LOOP;
END;
I have table with 100 columns with not correlated names (ABC1, DA23, EE123 - there is no common pattern there).
I want to iterate through every row and every column in this table.
My current script:
BEGIN
FOR single_row IN (
SELECT *
FROM MY_TABLE)
LOOP
--iterate through columns of 'single_row'
--for each nullable column do insert with real current column name and column value)
--I assume each column is nullable except of ID
INSERT INTO ANOTHER_TABLE VALUES (single_row.id, column_name, column_value);
END LOOP;
END;
So for example, if MY_TABLE contains 2 rows:
ID|ABC1|DA23|EE123|...
1|123|456|789|...
2|321|654|987|...
After running my script, my ANOTHER_TABLE will contain:
MY_TABLE_ID|COLUMN_NAME|COLUMN_VALUE
1|ABC1|123
1|DA23|456
1|EE123|789
... other columns from row 1
2|ABC1|321
2|DA23|654
2|EE123|987
... other columns from row 2
How I can do this?
I'm using Oracle 11g
EDIT
#vkp provided great solution, but there is one more thing to solve. I don't want to specify all columns in in clause. I would love to use some kind of query there or * or anything else, just to not be forced to list all of them.
I have tried something like this:
select *
from MY_TABLE t
unpivot (
column_value for column_name in (select column_name
from user_tab_columns
where table_name = 'MY_TABLE'
and nullable = 'Y')
) u
but it returns error:
ORA-00904: : invalid identifier
00904. 00000 - "%s: invalid identifier"
This is an application of unpivot.
select *
from my_table m
unpivot (column_value for column_name in (ABC1,DA23,EE123)) u
null values for any of the columns for an id won't be shown in the result.
If you have to include null values in the output, use the option INCLUDE NULLS.
select *
from my_table m
unpivot include nulls (column_value for column_name in (ABC1,DA23,EE123)) u
Edit: To include column names dynamically, use
DECLARE
sql_stmt VARCHAR2(4000);
var_columns VARCHAR2(4000); --use clob datatype if the column names can't fit in with this datatype
BEGIN
SELECT LISTAGG(column_name,',') WITHIN GROUP(ORDER BY column_name)
INTO var_columns
FROM user_tab_columns
WHERE table_name='MY_TABLE' AND column_name<>'ID';
sql_stmt:='select * from my_table m
unpivot
(column_value for column_name in (' || var_columns || ')) u';
EXECUTE IMMEDIATE sql_stmt;
END;
/
First option. With dynamic sql.
declare
v_ctx number;
v_query varchar2(500);
v_total NUMBER;
v_desctab DBMS_SQL.DESC_TAB;
v_column_cnt NUMBER;
v_value varchar2(32767);
v_result clob := '';
v_rownum number := 0;
begin
v_ctx := dbms_sql.open_cursor;
v_query := 'select * from user_objects where rownum < 100';
dbms_sql.parse(v_ctx,v_query,dbms_sql.v7);
v_total := dbms_sql.execute(v_ctx);
DBMS_SQL.DESCRIBE_COLUMNS(v_ctx, v_column_cnt, v_desctab);
for i in 1 .. v_column_cnt loop
dbms_sql.define_column(v_ctx, i, v_value /* data_type varchar2*/, 32767 /* max_length*/);
end loop;
loop
exit when dbms_sql.fetch_rows(v_ctx) = 0;
v_rownum := v_rownum +1;
for i in 1 .. v_column_cnt loop
dbms_sql.column_value(v_ctx, i, v_value);
dbms_output.put_line(v_rownum||' - '||v_desctab(i).col_name||' - '||v_value);
end loop;
end loop;
dbms_sql.close_cursor(v_ctx);
exception
when others then
dbms_sql.close_cursor(v_ctx);
raise;
end;
/
2nd option with xquery.
select t1.id,t2.* from xmltable('for $i in ora:view("<you_table_here>")/ROW
return $i'
columns id FOR ORDINALITY
, row_value xmltype path'.'
) t1
,xmltable('for $i in $row_value/ROW/* return $i'
passing t1.row_value as "row_value"
columns col_index for ORDINALITY ,
column_name varchar2(100) path 'name()',
column_value varchar2(100) path 'text()'
) t2
Here is a simple solution using REF CURSOR.
I've tried this code and it's working at my end.
DECLARE
query_2 VARCHAR2(1000);
TYPE icur IS REF CURSOR;
ic icur;
col_val VARCHAR2(100);
BEGIN
FOR j IN
(SELECT * FROM user_tab_cols WHERE table_name = UPPER('MY_TABLE'))
LOOP
dbms_output.put_line(j.column_name);
query_2 := 'SELECT ' || j.column_name|| ' FROM MY_TABLE';
OPEN ic FOR query_2;
LOOP
FETCH ic INTO col_val;
EXIT WHEN ic%NOTFOUND;
INSERT INTO ANOTHER_TABLE VALUES( j.column_name, col_val);
END LOOP;
END LOOP;
END;
/
I have the following procedure, which does not compile correctly, because it refers to non existing objects (table does not exist)
Here is only a section of the code (i used generic names for tables and columns):
DECLARE
C INTEGER := 0;
BEGIN
SELECT COUNT(1) INTO C FROM USER_TABLES WHERE TABLE_NAME = 'MY_TABLE';
IF C > 0 THEN
DECLARE
CURSOR c_maps IS SELECT COLUM_NAME1, COLUM_NAME2 FROM MY_TABLE WHERE ACTIVE = 1;
BEGIN
FOR prec IN c_maps LOOP
some code...;
END LOOP;
EXECUTE IMMEDIATE 'some code..';
END;
END IF;
END;
/
I don't know how to write this statement dynamically, since the table "MY_TABLE" does not exist:
CURSOR c_maps IS SELECT COLUM_NAME1, COLUM_NAME2 FROM MY_TABLE WHERE ACTIVE =1;
I also tried to write it like:
CURSOR c_maps IS SELECT COLUM_NAME1, COLUM_NAME2 FROM (Select 'MY_TABLE' from dual) WHERE ACTIVE = 1;
However, than it refers to the column "ACTIVE" which also does not exist at compile time...It is possible to write the whole procedure inside "execute immediate" - block? I have tried different variants, however without success
You may need to open the cursor in a different way, so that the non existing table is only referred in dynamic SQL; for example:
declare
c integer := 0;
curs sys_refcursor;
v1 number;
v2 number;
begin
select count(1)
into c
from user_tables
where table_name = 'MY_TABLE';
if c > 0
then
open curs for 'select column_name1, column_name2 from my_table where active = 1';
loop
fetch curs into v1, v2;
exit when curs%NOTFOUND;
dbms_output.put_line(v1 || ' - ' || v2);
end loop;
else
dbms_output.put_line('The table does not exist');
end if;
end;
/