Sometimes you want to count data in all tables on a database to get a feel for the orders of magnitude, but you cannot use the approximated example in How to speed up Count(*) in Interbase/Firebird – Stack Overflow as those require primary keys.
Then the below script can help: it generates the right queries as a union all ordering by the count in the tables.
Example generated code on C:\Program Files (x86)\Firebird\Firebird_2_5\examples\empbuild\EMPLOYEE.FDB:
SQL
--------------------------------------------------------------------------------------------------
select 128 as id, 'COUNTRY' as name, count(*) from "COUNTRY" union all
select 129 as id, 'JOB' as name, count(*) from "JOB" union all
select 130 as id, 'DEPARTMENT' as name, count(*) from "DEPARTMENT" union all
select 131 as id, 'EMPLOYEE' as name, count(*) from "EMPLOYEE" union all
select 133 as id, 'PROJECT' as name, count(*) from "PROJECT" union all
select 134 as id, 'EMPLOYEE_PROJECT' as name, count(*) from "EMPLOYEE_PROJECT" union all
select 135 as id, 'PROJ_DEPT_BUDGET' as name, count(*) from "PROJ_DEPT_BUDGET" union all
select 136 as id, 'SALARY_HISTORY' as name, count(*) from "SALARY_HISTORY" union all
select 137 as id, 'CUSTOMER' as name, count(*) from "CUSTOMER" union all
select 138 as id, 'SALES' as name, count(*) from "SALES" order by 3
Example output on C:\Program Files (x86)\Firebird\Firebird_2_5\examples\empbuild\EMPLOYEE.FDB:
| ID |
NAME |
COUNT |
| 133 |
PROJECT |
6 |
| 128 |
COUNTRY |
14 |
| 137 |
CUSTOMER |
15 |
| 130 |
DEPARTMENT |
21 |
| 135 |
PROJ_DEPT_BUDGET |
24 |
| 134 |
EMPLOYEE_PROJECT |
28 |
| 129 |
JOB |
31 |
| 138 |
SALES |
33 |
| 131 |
EMPLOYEE |
42 |
| 136 |
SALARY_HISTORY |
49 |
The generation code below uses a few tricks:
The rank helps me distinguish the last row (for the order by 3 clause) and other rows (for the union all clauses).
Generation code:
with tables(id, name) as (
-- http://www.firebirdfaq.org/faq376/
select r.RDB$RELATION_ID as id, trim(r.RDB$RELATION_NAME) as name
from RDB$RELATIONS r
where 1=1
and (r.RDB$SYSTEM_FLAG is null or r.RDB$SYSTEM_FLAG = 0)
and r.RDB$VIEW_BLR is null
order by 1
),
ranked_tables(id, rank, name) as (
-- http://www.firebirdfaq.org/faq343/
select tables.ID, count(others.id)+1 as "rank", tables.NAME
from tables
left join tables others on others.ID < tables.ID
group by "ID", "NAME"
order by "rank"
),
parts(id, rank, name, suffix) as (
select ranked_tables.id,
ranked_tables.rank,
ranked_tables.name,
case
when ranked_tables.rank = 1 then 'union all' -- first
when ranked_tables.rank = (select count(*) from tables) then 'order by 3' --last
else 'union all' -- middle
end as suffix
from ranked_tables
)
select -- parts.id, parts.rank, parts.name, parts.suffix,
'select '||parts.id||' as id, '''||parts.name||''' as name, count(*) from "'||parts.name||'" '||parts.suffix||'' as SQL
from parts
order by parts.id
–jeroen
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