Convert BigQuery's legacy SQL to standard SQL - google-bigquery

I want to convert below code from legacy to standard SQL. The code is in Legacy SQL (Big Query). Here is the code:
MAX(IF((hi.Info.Action='complete'),1, 0)) WITHIN RECORD AS transact
what will be the equivalent for standard SQL?

#legacySQL
SELECT
MAX(IF((hi.Info.Action='complete'),1, 0)) WITHIN RECORD AS transact
FROM table
will be
#standardSQL
SELECT
(SELECT MAX(IF(Info.Action='complete',1, 0)) FROM UNNEST(hi)) AS transact
FROM table
Note: I assumed that hi is REPEATED RECORD and info is RECORD

Related

Add a day to a date in Postgres and SQL Server

I'm looking to find a way to add a day to a date in both Postgres and SQL Server so I don't have to add an if condition checking which database the server is running
DATEADD(day, 1, STOP_DATE)
doesn't work in PostgreSQL &
STOP_DATE + 1
doesnt work in sql server
Overall, it is not a good idea to try to write SQL code using syntax that is common on both SQL Server and Postgres. You are severely limiting yourself and will sooner or later come across a query that runs too slowly because it doesn't use syntax specific to one of the DBMS.
For example, with your approach you are artificially refusing to use lateral joins, because their syntax is different in Postgres (LATERAL JOIN) and SQL Server (CROSS/OUTER APPLY).
Back to your question.
You can add an integer value to a date value in Postgres and to datetime value in SQL Server.
SQL Server
CREATE TABLE T(d datetime);
INSERT INTO T VALUES ('2020-01-01');
SELECT
d, d+1 AS NextDay
FROM T
http://sqlfiddle.com/#!18/d519d9/1
This will not work with date or datetime2 data types in SQL Server, only datetime.
Postgres
CREATE TABLE T(d date);
INSERT INTO T VALUES ('2020-01-01');
SELECT
d, d+1 AS NextDay
FROM T
http://sqlfiddle.com/#!17/b9670/2
I don't know if it will work with other data types.
Define a function in PostgreSQL that works like the sql server function.
Edit:
can't pass day
Create a function with the same name on each database system that adds a day accordingly.

Convert DB2 SQL query to SQL Server

I have to convert a DB2 query to SQL Server, but don't understand what exactly below query does:
SELECT
t.MyColumnA NAME(MyColumnA-01),
t.MyColumnA COLHDG("COA" "VALUE")
FROM
MyTable t
It looks like the NAME and COLHDG functions are just UI functions specific to HelpSystems. The actual query would be
SELECT t.MyColumnA AS "COA VALUE"
FROM MyTable t

Using SQL Open Query on Oracle Server, Date overflow?

I'm querying an Oracle server using OPENQUERY. The issue I'm running into is when I execute my query, the date returned from Oracle. For example
SELECT * FROM OPENQUERY(ORACLE,
'SELECT * FROM ORACLE.some_table
WHERE date >'01-Jan-2016')
Will return a different number of rows than when I run the same query in Oracle. It also returns a date column with a large selection of dates listed as '4712-DEC-31'

Equivalent to minus in netezza

I want to compare data between two different db tables in netezza. In oracle we can do that by minus operator. How can the same operation be done in netezza.
SELECT CUSTOMER_SRC_ID,CUSTOMER_SRC_DESC FROM CIDB_SIT..CUSTOMER_SRC
MINUS
SELECT CUSTOMER_SRC_ID,CUSTOMER_SRC_DESC FROM EDW_SIT..CUSTOMER_SRC
Seems like it doesn't work in netezza. Can any one help me find the equivalent query in netezza?
The ANSI-SQL standard calls this operators except. Netezza implements it, as do PostgreSQL and MS SQL Server:
SELECT CUSTOMER_SRC_ID,CUSTOMER_SRC_DESC FROM CIDB_SIT..CUSTOMER_SRC
EXCEPT -- Here
SELECT CUSTOMER_SRC_ID,CUSTOMER_SRC_DESC FROM EDW_SIT..CUSTOMER_SRC
You could use the EXCEPT
or
--if customer_src_id is unique--
SELECT CUSTOMER_SRC_ID,CUSTOMER_SRC_DESC
FROM CIDB_SIT..CUSTOMER_SRC
WHERE CUSTOMER_SRC_ID NOT IN (SELECT CUSTOMER_SRC_ID FROM EDW_SIT..CUSTOMER_SRC);

SQL to return fixed data in both SQL Server and Oracle

I need a common select statement that returns a fixed value / row without the need of tables, which has to work with both Oracle & Sql Server.
eg for Oracle I know I can use:
select 'O' AS INDICATOR from DUAL;
But this won't work on Sql Server.
Can this be done with the same SQL on both Oracle & SQL Server?
AFAIK, you'll need different queries, unless you can find a table that exists both on the SQL Server and on the Oracle Server.
Oracle uses the DUAL table for dummy queries, while the syntax to just select a constant on SQL server is a bit simpler:
select 'O' as Indicator
will return a one-row recordset.
P.S. If you intend to write just standard SQL and have it work on both SQL Server and Oracle, note that there are lots and lots of differences, even if you do not use database-side code (stored procedures and functions).
Off the top of my head, some things that are different:
Case statement syntax
NVL vs IsNull
Null sorting behaviour
Data conversion functions
String manipulation functions
etc, etc.
You can't select data in Oracle without from statement. So you need to have a table in Oracle (common practice is to use standard table - Dual). The best solution if you really need to run same query on both database servers is to create Dual table with only one row in MS SQL. But really it's better to use different queries for different servers (maybe via some abstraction layer).
Use a common table expression (CTE) e.g.
WITH D (INDICATOR)
AS
(
SELECT *
FROM (
VALUES ('O')
) T (c1)
)
SELECT INDICATOR
FROM D;
Or more simply in line:
SELECT *
FROM (
VALUES ('O')
) D (INDICATOR)
You can create the DUAL table in SQL Server:
CREATE TABLE DUAL (DUMMY NVARCHAR(1) NOT NULL);
INSERT INTO DUAL VALUES ('X');
and then use the same query as in Oracle:
select 'O' AS INDICATOR from DUAL;