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How to search a specific value in all tables (PostgreSQL)?

Is it possible to 开发者_如何学JAVAsearch every column of every table for a particular value in PostgreSQL?

A similar question is available here for Oracle.


How about dumping the contents of the database, then using grep?

$ pg_dump --data-only --inserts -U postgres your-db-name > a.tmp
$ grep United a.tmp
INSERT INTO countries VALUES ('US', 'United States');
INSERT INTO countries VALUES ('GB', 'United Kingdom');

The same utility, pg_dump, can include column names in the output. Just change --inserts to --column-inserts. That way you can search for specific column names, too. But if I were looking for column names, I'd probably dump the schema instead of the data.

$ pg_dump --data-only --column-inserts -U postgres your-db-name > a.tmp
$ grep country_code a.tmp
INSERT INTO countries (iso_country_code, iso_country_name) VALUES ('US', 'United  States');
INSERT INTO countries (iso_country_code, iso_country_name) VALUES ('GB', 'United Kingdom');


Here's a pl/pgsql function that locates records where any column contains a specific value. It takes as arguments the value to search in text format, an array of table names to search into (defaults to all tables) and an array of schema names (defaults all schema names).

It returns a table structure with schema, name of table, name of column and pseudo-column ctid (non-durable physical location of the row in the table, see System Columns)

CREATE OR REPLACE FUNCTION search_columns(
    needle text,
    haystack_tables name[] default '{}',
    haystack_schema name[] default '{}'
)
RETURNS table(schemaname text, tablename text, columnname text, rowctid text)
AS $$
begin
  FOR schemaname,tablename,columnname IN
      SELECT c.table_schema,c.table_name,c.column_name
      FROM information_schema.columns c
        JOIN information_schema.tables t ON
          (t.table_name=c.table_name AND t.table_schema=c.table_schema)
        JOIN information_schema.table_privileges p ON
          (t.table_name=p.table_name AND t.table_schema=p.table_schema
              AND p.privilege_type='SELECT')
        JOIN information_schema.schemata s ON
          (s.schema_name=t.table_schema)
      WHERE (c.table_name=ANY(haystack_tables) OR haystack_tables='{}')
        AND (c.table_schema=ANY(haystack_schema) OR haystack_schema='{}')
        AND t.table_type='BASE TABLE'
  LOOP
    FOR rowctid IN
      EXECUTE format('SELECT ctid FROM %I.%I WHERE cast(%I as text)=%L',
       schemaname,
       tablename,
       columnname,
       needle
      )
    LOOP
      -- uncomment next line to get some progress report
      -- RAISE NOTICE 'hit in %.%', schemaname, tablename;
      RETURN NEXT;
    END LOOP;
 END LOOP;
END;
$$ language plpgsql;

See also the version on github based on the same principle but adding some speed and reporting improvements.

Examples of use in a test database:

  • Search in all tables within public schema:
select * from search_columns('foobar');
 schemaname | tablename | columnname | rowctid 
------------+-----------+------------+---------
 public     | s3        | usename    | (0,11)
 public     | s2        | relname    | (7,29)
 public     | w         | body       | (0,2)
(3 rows)
  • Search in a specific table:
 select * from search_columns('foobar','{w}');
 schemaname | tablename | columnname | rowctid 
------------+-----------+------------+---------
 public     | w         | body       | (0,2)
(1 row)
  • Search in a subset of tables obtained from a select:
select * from search_columns('foobar', array(select table_name::name from information_schema.tables where table_name like 's%'), array['public']);
 schemaname | tablename | columnname | rowctid 
------------+-----------+------------+---------
 public     | s2        | relname    | (7,29)
 public     | s3        | usename    | (0,11)
(2 rows)
  • Get a result row with the corresponding base table and and ctid:
select * from public.w where ctid='(0,2)';
 title |  body  |         tsv         
-------+--------+---------------------
 toto  | foobar | 'foobar':2 'toto':1

Variants

  • To test against a regular expression instead of strict equality, like grep, this part of the query:

    SELECT ctid FROM %I.%I WHERE cast(%I as text)=%L

    may be changed to:

    SELECT ctid FROM %I.%I WHERE cast(%I as text) ~ %L

  • For case insensitive comparisons, you could write:

    SELECT ctid FROM %I.%I WHERE lower(cast(%I as text)) = lower(%L)


to search every column of every table for a particular value

This does not define how to match exactly.
Nor does it define what to return exactly.

Assuming:

  • Find any row with any column containing the given value in its text representation - as opposed to equaling the given value.
  • Return the table name (regclass) and the tuple ID (ctid), because that's simplest.

Here is a dead simple, fast and slightly dirty way:

CREATE OR REPLACE FUNCTION search_whole_db(_like_pattern text)
  RETURNS TABLE(_tbl regclass, _ctid tid) AS
$func$
BEGIN
   FOR _tbl IN
      SELECT c.oid::regclass
      FROM   pg_class c
      JOIN   pg_namespace n ON n.oid = relnamespace
      WHERE  c.relkind = 'r'                           -- only tables
      AND    n.nspname !~ '^(pg_|information_schema)'  -- exclude system schemas
      ORDER BY n.nspname, c.relname
   LOOP
      RETURN QUERY EXECUTE format(
         'SELECT $1, ctid FROM %s t WHERE t::text ~~ %L'
       , _tbl, '%' || _like_pattern || '%')
      USING _tbl;
   END LOOP;
END
$func$  LANGUAGE plpgsql;

Call:

SELECT * FROM search_whole_db('mypattern');

Provide the search pattern without enclosing %.

Why slightly dirty?

If separators and decorators for the row in text representation can be part of the search pattern, there can be false positives:

  • column separator: , by default
  • whole row is enclosed in parentheses:()
  • some values are enclosed in double quotes "
  • \ may be added as escape char

And the text representation of some columns may depend on local settings - but that ambiguity is inherent to the question, not to my solution.

Each qualifying row is returned once only, even when it matches multiple times (as opposed to other answers here).

This searches the whole DB except for system catalogs. Will typically take a long time to finish. You might want to restrict to certain schemas / tables (or even columns) like demonstrated in other answers. Or add notices and a progress indicator, also demonstrated in another answer.

The regclass object identifier type is represented as table name, schema-qualified where necessary to disambiguate according to the current search_path:

  • Find the referenced table name using table, field and schema name

What is the ctid?

  • How do I decompose ctid into page and row numbers?

You might want to escape characters with special meaning in the search pattern. See:

  • Escape function for regular expression or LIKE patterns


There is a way to achieve this without creating a function or using an external tool. By using Postgres' query_to_xml() function that can dynamically run a query inside another query, it's possible to search a text across many tables. This is based on my answer to retrieve the rowcount for all tables:

To search for the string foo across all tables in a schema, the following can be used:

with found_rows as (
  select format('%I.%I', table_schema, table_name) as table_name,
         query_to_xml(format('select to_jsonb(t) as table_row 
                              from %I.%I as t 
                              where t::text like ''%%foo%%'' ', table_schema, table_name), 
                      true, false, '') as table_rows
  from information_schema.tables 
  where table_schema = 'public'
)
select table_name, x.table_row
from found_rows f
  left join xmltable('//table/row' 
                     passing table_rows
                       columns
                         table_row text path 'table_row') as x on true

Note that the use of xmltable requires Postgres 10 or newer. For older Postgres version, this can be also done using xpath().

with found_rows as (
  select format('%I.%I', table_schema, table_name) as table_name,
         query_to_xml(format('select to_jsonb(t) as table_row 
                              from %I.%I as t 
                              where t::text like ''%%foo%%'' ', table_schema, table_name), 
                      true, false, '') as table_rows
  from information_schema.tables 
  where table_schema = 'public'
)
select table_name, x.table_row
from found_rows f
   cross join unnest(xpath('/table/row/table_row/text()', table_rows)) as r(data)

The common table expression (WITH ...) is only used for convenience. It loops through all tables in the public schema. For each table the following query is run through the query_to_xml() function:

select to_jsonb(t)
from some_table t
where t::text like '%foo%';

The where clause is used to make sure the expensive generation of XML content is only done for rows that contain the search string. This might return something like this:

<table xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<row>
  <table_row>{"id": 42, "some_column": "foobar"}</table_row>
</row>
</table>

The conversion of the complete row to jsonb is done, so that in the result one could see which value belongs to which column.

The above might return something like this:

table_name   |   table_row
-------------+----------------------------------------
public.foo   |  {"id": 1, "some_column": "foobar"}
public.bar   |  {"id": 42, "another_column": "barfoo"}

Online example for Postgres 10+

Online example for older Postgres versions


Without storing a new procedure you can use a code block and execute to obtain a table of occurences. You can filter results by schema, table or column name.

DO $$
DECLARE
  value int := 0;
  sql text := 'The constructed select statement';
  rec1 record;
  rec2 record;
BEGIN
  DROP TABLE IF EXISTS _x;
  CREATE TEMPORARY TABLE _x (
    schema_name text, 
    table_name text, 
    column_name text,
    found text
  );
  FOR rec1 IN 
        SELECT table_schema, table_name, column_name
        FROM information_schema.columns 
        WHERE table_name <> '_x'
                AND UPPER(column_name) LIKE UPPER('%%')                  
                AND table_schema <> 'pg_catalog'
                AND table_schema <> 'information_schema'
                AND data_type IN ('character varying', 'text', 'character', 'char', 'varchar')
        LOOP
    sql := concat('SELECT ', rec1."column_name", ' AS "found" FROM ',rec1."table_schema" , '.',rec1."table_name" , ' WHERE UPPER(',rec1."column_name" , ') LIKE UPPER(''','%my_substring_to_find_goes_here%' , ''')');
    RAISE NOTICE '%', sql;
    BEGIN
        FOR rec2 IN EXECUTE sql LOOP
            RAISE NOTICE '%', sql;
            INSERT INTO _x VALUES (rec1."table_schema", rec1."table_name", rec1."column_name", rec2."found");
        END LOOP;
    EXCEPTION WHEN OTHERS THEN
    END;
  END LOOP;
  END; $$;

SELECT * FROM _x;


If you're using IntelliJ add your DB to Database view then right click on databases and select full text search, it will list all tables and all fields for your specific text.


And if someone think it could help. Here is @Daniel Vérité's function, with another param that accept names of columns that can be used in search. This way it decrease the time of processing. At least in my test it reduced a lot.

CREATE OR REPLACE FUNCTION search_columns(
    needle text,
    haystack_columns name[] default '{}',
    haystack_tables name[] default '{}',
    haystack_schema name[] default '{public}'
)
RETURNS table(schemaname text, tablename text, columnname text, rowctid text)
AS $$
begin
  FOR schemaname,tablename,columnname IN
      SELECT c.table_schema,c.table_name,c.column_name
      FROM information_schema.columns c
      JOIN information_schema.tables t ON
        (t.table_name=c.table_name AND t.table_schema=c.table_schema)
      WHERE (c.table_name=ANY(haystack_tables) OR haystack_tables='{}')
        AND c.table_schema=ANY(haystack_schema)
        AND (c.column_name=ANY(haystack_columns) OR haystack_columns='{}')
        AND t.table_type='BASE TABLE'
  LOOP
    EXECUTE format('SELECT ctid FROM %I.%I WHERE cast(%I as text)=%L',
       schemaname,
       tablename,
       columnname,
       needle
    ) INTO rowctid;
    IF rowctid is not null THEN
      RETURN NEXT;
    END IF;
 END LOOP;
END;
$$ language plpgsql;

Bellow is an example of usage of the search_function created above.

SELECT * FROM search_columns('86192700'
    , array(SELECT DISTINCT a.column_name::name FROM information_schema.columns AS a
            INNER JOIN information_schema.tables as b ON (b.table_catalog = a.table_catalog AND b.table_schema = a.table_schema AND b.table_name = a.table_name)
        WHERE 
            a.column_name iLIKE '%cep%' 
            AND b.table_type = 'BASE TABLE'
            AND b.table_schema = 'public'
    )

    , array(SELECT b.table_name::name FROM information_schema.columns AS a
            INNER JOIN information_schema.tables as b ON (b.table_catalog = a.table_catalog AND b.table_schema = a.table_schema AND b.table_name = a.table_name)
        WHERE 
            a.column_name iLIKE '%cep%' 
            AND b.table_type = 'BASE TABLE'
            AND b.table_schema = 'public')
);


Here's @Daniel Vérité's function with progress reporting functionality. It reports progress in three ways:

  1. by RAISE NOTICE;
  2. by decreasing value of supplied {progress_seq} sequence from {total number of colums to search in} down to 0;
  3. by writing the progress along with found tables into text file, located in c:\windows\temp\{progress_seq}.txt.

_

CREATE OR REPLACE FUNCTION search_columns(
    needle text,
    haystack_tables name[] default '{}',
    haystack_schema name[] default '{public}',
    progress_seq text default NULL
)
RETURNS table(schemaname text, tablename text, columnname text, rowctid text)
AS $$
DECLARE
currenttable text;
columnscount integer;
foundintables text[];
foundincolumns text[];
begin
currenttable='';
columnscount = (SELECT count(1)
      FROM information_schema.columns c
      JOIN information_schema.tables t ON
        (t.table_name=c.table_name AND t.table_schema=c.table_schema)
      WHERE (c.table_name=ANY(haystack_tables) OR haystack_tables='{}')
        AND c.table_schema=ANY(haystack_schema)
        AND t.table_type='BASE TABLE')::integer;
PERFORM setval(progress_seq::regclass, columnscount);

  FOR schemaname,tablename,columnname IN
      SELECT c.table_schema,c.table_name,c.column_name
      FROM information_schema.columns c
      JOIN information_schema.tables t ON
        (t.table_name=c.table_name AND t.table_schema=c.table_schema)
      WHERE (c.table_name=ANY(haystack_tables) OR haystack_tables='{}')
        AND c.table_schema=ANY(haystack_schema)
        AND t.table_type='BASE TABLE'
  LOOP
    EXECUTE format('SELECT ctid FROM %I.%I WHERE cast(%I as text)=%L',
       schemaname,
       tablename,
       columnname,
       needle
    ) INTO rowctid;
    IF rowctid is not null THEN
      RETURN NEXT;
      foundintables = foundintables || tablename;
      foundincolumns = foundincolumns || columnname;
      RAISE NOTICE 'FOUND! %, %, %, %', schemaname,tablename,columnname, rowctid;
    END IF;
         IF (progress_seq IS NOT NULL) THEN 
        PERFORM nextval(progress_seq::regclass);
    END IF;
    IF(currenttable<>tablename) THEN  
    currenttable=tablename;
     IF (progress_seq IS NOT NULL) THEN 
        RAISE NOTICE 'Columns left to look in: %; looking in table: %', currval(progress_seq::regclass), tablename;
        EXECUTE 'COPY (SELECT unnest(string_to_array(''Current table (column ' || columnscount-currval(progress_seq::regclass) || ' of ' || columnscount || '): ' || tablename || '\n\nFound in tables/columns:\n' || COALESCE(
        (SELECT string_agg(c1 || '/' || c2, '\n') FROM (SELECT unnest(foundintables) AS c1,unnest(foundincolumns) AS c2) AS t1)
        , '') || ''',''\n''))) TO ''c:\WINDOWS\temp\' || progress_seq || '.txt''';
    END IF;
    END IF;
 END LOOP;
END;
$$ language plpgsql;


-- Below function will list all the tables which contain a specific string in the database

 select TablesCount(‘StringToSearch’);

--Iterates through all the tables in the database

CREATE OR REPLACE FUNCTION **TablesCount**(_searchText TEXT)
RETURNS text AS 
$$ -- here start procedural part
   DECLARE _tname text;
   DECLARE cnt int;
   BEGIN
    FOR _tname IN SELECT table_name FROM information_schema.tables where table_schema='public' and table_type='BASE TABLE'  LOOP
         cnt= getMatchingCount(_tname,Columnames(_tname,_searchText));
                                RAISE NOTICE 'Count% ', CONCAT('  ',cnt,' Table name: ', _tname);
                END LOOP;
    RETURN _tname;
   END;
$$ -- here finish procedural part
LANGUAGE plpgsql; -- language specification

-- Returns the count of tables for which the condition is met. -- For example, if the intended text exists in any of the fields of the table, -- then the count will be greater than 0. We can find the notifications -- in the Messages section of the result viewer in postgres database.

CREATE OR REPLACE FUNCTION **getMatchingCount**(_tname TEXT, _clause TEXT)
RETURNS int AS 
$$
Declare outpt text;
    BEGIN
    EXECUTE 'Select Count(*) from '||_tname||' where '|| _clause
       INTO outpt;
       RETURN outpt;
    END;
$$ LANGUAGE plpgsql;

--Get the fields of each table. Builds the where clause with all columns of a table.

CREATE OR REPLACE FUNCTION **Columnames**(_tname text,st text)
RETURNS text AS 
$$ -- here start procedural part
DECLARE
                _name text;
                _helper text;
   BEGIN
                FOR _name IN SELECT column_name FROM information_schema.Columns WHERE table_name =_tname LOOP
                                _name=CONCAT('CAST(',_name,' as VarChar)',' like ','''%',st,'%''', ' OR ');
                                _helper= CONCAT(_helper,_name,' ');
                END LOOP;
                RETURN CONCAT(_helper, ' 1=2');

   END;
$$ -- here finish procedural part
LANGUAGE plpgsql; -- language specification
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