SQLite: replace result values using bijective table - sqlite

In SQLite, I have the following query
SELECT x.nameIndex, y.nameIndex
FROM relation x, relation y
WHERE x.label=y.label AND x.feature=1 AND y.feature=0;
which returns all pairs of x.nameIndex,y.nameIndex with the same label where x has feature 1 and y has feature 0.
Now I have another table index2name where I store the name for each index, where I could do like:
SELECT name FROM index2name WHERE nameIndex=...;
How can I change the top query such that it looks up the name for the respective indeces and returns pairs of names instead?

Use a CTE which returns the name instead of the indexes and the group for each row in relation (by a join to index2name) and do a self join on that:
WITH cte AS (
SELECT i.name, r.label, r.feature
FROM relation r INNER JOIN index2name i
ON i.nameIndex = r.nameIndex
)
SELECT c1.name, c2.name
FROM cte c1 INNER JOIN cte c2
ON c2.label = c1.label
WHERE c1.feature=1 AND c2.feature=0;
Or without the CTE:
SELECT i1.name, i2.name
FROM relation r1 INNER JOIN relation r2
ON r2.label = r1.label
INNER JOIN index2name i1 ON i1.nameIndex = r1.nameIndex
INNER JOIN index2name i2 ON i2.nameIndex = r2.nameIndex
WHERE r1.feature=1 AND r2.feature=0;

Related

Is it possible to compare value to multiple columns in ''In'' clause?

select m.value
from MY_TABLE m
where m.value in (select m2.some_third_value, m2.some_fourth_value
from MY_TABLE_2 m2
where m2.first_val member of v_my_array
or m2.second_val member of v_my_array_2)
Is it possible to write a select similar to this, where m.value is compared to two columns and has to match at least one of those? Something like where m.value in (select m2.first_val, m2.second_val). Or is writing two separate selects unavoidable here?
No. When there are multiple columns in the IN clause, there must be the same number of columns in the WHERE clause. The pairwise query compares each record in the WHERE clause against the records returned by the sub-query. The statement below
SELECT *
FROM table_main m
WHERE ( m.col_1, m.col_2 ) IN (SELECT s.col_a,
s.col_b
FROM table_sub s)
is equivalent to
SELECT *
FROM table_main m
WHERE EXISTS (SELECT 1
FROM table_sub s
WHERE m.col_1 = s.col_a
AND m.col_2 = s.col_b)
The only way to search both columns in one SELECT statement would be to OUTER JOIN the second table to the first table.
SELECT m.*
FROM table_main m
LEFT JOIN table_sub s ON (m.col_1 = s.col_a OR m.col_1 = s.col_b)
WHERE m.col_1 = s.col_a
OR m.col_1 = s.col_b

No more spool space in Teradata while trying Update

I'm trying to update a table with to many rows 388.000.
This is the query:
update DL_RG_ANALYTICS.SH_historico
from
(
SELECT
CAST((MAX_DIA - DIA_PAGO) AS INTEGER) AS DIAS_AL_CIERRE_1
FROM
(SELECT * FROM DL_RG_ANALYTICS.SH_historico A
LEFT JOIN
(SELECT ANO||MES AS ANO_MES, MAX(DIA) AS MAX_DIA FROM DL_RG_ANALYTICS.SH_CALENDARIO
GROUP BY 1) B
ON A.ANOMES = B.ANO_MES
) M) N
SET DIAS_AL_CIERRE = DIAS_AL_CIERRE_1;
Any help is apreciate.
This first thing I'd do is replace the SELECT * with only the columns you need. You can also remove the M derived table to make it easier to read:
UPDATE DL_RG_ANALYTICS.SH_historico
FROM (
SELECT CAST((MAX_DIA - DIA_PAGO) AS INTEGER) AS DIAS_AL_CIERRE_1
FROM DL_RG_ANALYTICS.SH_historico A
LEFT JOIN (
SELECT ANO || MES AS ANO_MES, MAX(DIA) AS MAX_DIA
FROM DL_RG_ANALYTICS.SH_CALENDARIO
GROUP BY 1
) B ON A.ANOMES = B.ANO_MES
) N
SET DIAS_AL_CIERRE = DIAS_AL_CIERRE_1;
What indexes are defined on the SH_CALENDARIO table? If there is a composite index of (ANO, MES) then you should re-write your LEFT JOIN sub-query to GROUP BY these two columns since you concatenate them together anyways. In general, you want to perform joins, GROUP BY and OLAP functions on indexes, so there will be less row re-distribution and they will run more efficiently.
Also, this query is updating all rows in the table with the same value. Is this intended, or do you want to include extra columns in your WHERE clause?

PL SQL nested subquery

I'm trying to get the result into a variable (is it possible to do it as a %rowtype of an existing table? probably not because of conflicting columns) where it would display me all the values where the two refs overlap and the i_ref(which is inputted ) also overlaps with the ref from t1.
select *
into aRow
from table1 t1
where t1.ref = i_ref
and (select * from table2 t2 where t1.ref = t2.ref);
What am I doing wrong with my select?
You can join tables instead of nested subquery:
select t1.*
into aRow
from table1 t1 join table2 t2 on t1.ref = t2.ref
where t1.ref = i_ref

SQLITE, Create a temp table then select from it

just wondering how i can create a temp table and then select from it further down the script.
Example.
CREATE TEMPORARY TABLE TEMP_TABLE1 AS
Select
L.ID,
SUM(L.cost)/2 as Costs,
from Table1 L
JOIN Table2 C on L.ID = C.ID
Where C.name = 'mike'
Group by L.ID
Select
Count(L.ID)
from Table1 L
JOIN TEMP_TABLE1 TT1 on L.ID = TT1.ID;
Where L.ID not in (TT1)
And Sum(L.Cost) > TT1.Costs
Ideally I want to have a temp table then use it later in the script to reference from.
Any help would be great!
You simply refer to the table as temp.<table> or <table> the latter only if it is a unique table name.
As per :-
If a schema-name is specified, it must be either "main", "temp", or
the name of an attached database. In this case the new table is
created in the named database. If the "TEMP" or "TEMPORARY" keyword
occurs between the "CREATE" and "TABLE" then the new table is created
in the temp database. It is an error to specify both a schema-name and
the TEMP or TEMPORARY keyword, unless the schema-name is "temp". If no
schema name is specified and the TEMP keyword is not present then the
table is created in the main database.
SQL As Understood By SQLite - CREATE TABLE
The following example creates 3 tables :-
table1 with 3 columns as a permanent table.
table1 a temporary copy of the permanent table1.
temp_table another temporary copy of the permanent table1.
:-
DROP TABLE IF EXISTS temp.table1;
DROP TABLE IF EXISTS table1;
DROP TABLE IF EXISTS temp_table;
CREATE TABLE table1 (columnA INTEGER,columnB INTEGER, columnC INTEGER);
When creating the permanent table 1 it is loaded with 4 rows
:-
INSERT INTO table1 (columnA,columnB,columnC) VALUES
(1,5,20),
(2,7,21),
(3,8,80),
(4,3,63);
CREATE TEMP TABLE table1 AS select * from table1;;
CREATE TEMPORARY TABLE temp_table AS SELECT * FROM table1;
both temp tables are then used to in a union all to basically duplicate the rows, but with an indicator of the source table as a new column from_table
Not that two forms of referring to the temp tables are used. temp. and just the table name.
The latter only usable if the temporary table is a unique table name.
:-
SELECT 'temp_table' AS from_table,* FROM temp_table
UNION ALL
SELECT 'temp.table1' as from_table,* FROM temp.table1;
The result being :-
Re addition of example :-
CREATE TEMPORARY TABLE TEMP_TABLE1 AS
Select
L.ID,
SUM(L.cost)/2 as Costs,
from Table1 L
JOIN Table2 C on L.ID = C.ID
Where C.name = 'mike'
Group by L.ID
Select
Count(L.ID)
from Table1 L
JOIN TEMP_TABLE1 TT1 on L.ID = TT1.ID;
Where L.ID not in (TT1)
And Sum(L.Cost) > TT1.Costs
There are a few issues with this example bar the misuse of the aggregate (commented out) the following works.
Note for my convenience I've added an _ to the table names.
:-
DROP TABLE IF EXISTS Table_1;
DROP TABLE IF EXISTS Table_2;
DROP TABLE If EXISTS temp.temp_table1;
CREATE TABLE Table_1 (ID INTEGER PRIMARY KEY, cost REAL);
CREATE TABLE Table_2 (ID INTEGER PRIMARY KEY, name TEXT);
INSERT INTO Table_1 (cost) VALUES (100.45),(56.78),(99.99);
INSERT INTO Table_2 (name) VALUES ('mike'),('mike'),('fred');
CREATE TEMP TABLE temp_table1 AS
SELECT L.ID,
sum(L.cost)/2 as Costs
FROM Table_1 L
JOIN Table_2 C ON L.ID = C.ID
WHERE C.name = 'mike'
GROUP BY L.ID;
SELECT
count(L.ID)
FROM Table_1 L
JOIN temp_table1 TT1 ON L.ID = TT1.[L.ID]
WHERE
L.ID NOT IN (TT1.[L.ID])
-- AND Sum(L.cost) > TT1.costs --<<<< misuse of aggregate
The issues are based upon the column name being L.ID so this has to be enclosed (rules here SQL As Understood By SQLite - SQLite Keywords apply) [ and ] have been used above.
of course you could circumvent the need for enclosure by naming the column using AS e..g SELECT
L.ID AS lid, --<<<< AS lid ADDED
SUM(L.cost)/2 as Costs, ,.......
Adding the following may be suitable for getting around the misuse of aggregate :-
GROUP BY L.ID
HAVING sum(L.cost) > TT1.costs
Adding the following to the end of the script :-
SELECT
count(L.ID), *
FROM Table_1 L
JOIN temp_table1 TT1 ON L.ID = TT1.[L.ID];
results in :-
If this is only to be used by one SELECT statement then you can use the WITH clause:
WITH TmpTable(id,cost) AS
(
...SELECT statement that returns the two columns (id and cost)...
)
SELECT id, cost FROM TmpTable WHERE ...;

Drupal db_query get all rows

I'm starting to build themes for Drupal.
I have a question about drupal queries, but I didn't find any answer...
I have a db_query in one of my modules, but only return a few rows (13 rows always, and table has 20) How can I select all rows from one table?
My query is like this
$result = db_query("SELECT * FROM bv_calendar c INNER JOIN bv_countries p ON c.country_id = p.country_id INNER JOIN bv_vaccinate v ON c.vaccinate_id = v.vaccinate_id ORDER BY $orderby ASC");
while ($class = $result->fetchAssoc()) {
$classes[$class["calendar_id"]] = $class;
}
How can I get all rows?
Thank you
From the looks of it I'd say you're not getting all the rows from the *bv_calendar* because you're using INNER JOIN on your SQL query which requires to be matching records on your *bv_countries* and *bv_vaccinate* tables.
Try replacing the INNER JOIN for LEFT JOIN as in the later "If there is no matching row for the right table in the ON or USING part in a LEFT JOIN, a row with all columns set to NULL is used for the right table." from http://dev.mysql.com/doc/refman/5.0/en/join.html.
If that's the result you want then your SQL query should be:
SELECT * FROM bv_calendar c LEFT JOIN bv_countries p ON c.country_id = p.country_id LEFT JOIN bv_vaccinate v ON c.vaccinate_id = v.vaccinate_id ORDER BY $orderby ASC

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