I have the following JOIN:
SELECT * FROM tableA INNER JOIN tableB USING (commonColumn)
I get an error:
"commonColumn" is not a recognized table hints option. If it is
intended as a parameter to a table-valued function or to the
CHANGETABLE function, ensure that your database compatibility mode is
set to 90.
The following instead works:
SELECT * FROM tableA INNER JOIN tableB ON tableA.commonColumn = tableB.commonColumn
The compatibility level in my case is set to 100 (SQL Server 2008), while, by the way, I am working with SQL Server 2012.
What am I doing wrong? I find it very difficult to find example of the use of the keyword USING, as it is almost impossible to do a relevant web search. Yet, it seems the right thing to use when the "joining columns" have the same name...
USING is not supported SQL Server syntax. It's not a reserved keyword, either, so the query engine is using that as a table alias.
It is an ODBC keyword, but those are handled somewhat differently. The engine won't always complain if you use them, but you're not supposed to use them anyways.
It is also listed as a possible future reserved keyword. It's common for new editions of SQL Server to add words to the core reserved list.
Personally, I don't see them adding NATURAL JOIN syntax support, even with USING. A lot of DBAs consider NATURAL JOINs problematic.
The USING keyword is used to specify the source data for MERGE statements (called <table source>) in the documentation.
Related
tl;dr: Hibernate automatically generates SQL table aliases in its queries like jurisdicti4_ or this_. Here's an example query:
SELECT
this_.id AS id2_6_3_,
this_.a_table_column AS a_table_column3_6_3_,
jurisdicti4_.b_table_column AS b_table_column4_6_3_,
FROM
app_table_a this_
LEFT OUTER JOIN jurisdiction jurisdicti4_ ON this_.jurisdiction = jurisdicti4_.name
WHERE
this_.a_table_column = ?
I'm using the Hibernate Criteria API to add some hints that need reference the SQL aliases in the query, so I need to know how to either:
specify the SQL table aliases Hibernate will use in its queries (e.g. tell it to use juris instead of jurisdicti4_ for jurisdiction, or
get hibernate to tell me the exact SQL table alias it will use for a particular table or entity (e.g. be told the alias in the query for jurisdiction will be jurisdicti4_.
Full story:
I've inherited a Java app with an Oracle DB that uses Hibernate 4.3.8 and the Hibernate Criteria API to generate some complicated search queries. It recently ran into a severe SQL performance problem that will require us to start to include hints these queries. However, we use Oracle, and its index hints are in the form of:
/*+ index (TABLE_ALIAS INDEX_NAME) */
I've successfully added the needed hints using Criteria.addHint(...), however I've had to hardcode the Hibernate-generated TABLE_ALIAS in the hint string. I'm concerned that over time, the aliases may change, so I want to either control how they're generated or be able to retrieve their values to use when adding the SQL hint.
Edit: This website describes the Hibernate SQL alias generation process: https://prismoskills.appspot.com/lessons/Hibernate/Chapter_23_-_Hibernate_alias_names.jsp
I've found that I have partial control of the SQL aliases when I programmatically set up the join like this: criteria.createAlias(associationPath, alias). The alias value I pass seems to be used as the first part of the SQL alias for the table. However, Hibernate appends some kind of generated table ID integer to that, so I'd get something like myalias4_ in the generated SQL. Also, this only seems to work in joins I setup myself in the criteria. Hibernate will often add its own based on the mappings, and I'm not sure how get this same level of partial control over those.
I'm working in a project where I have been explicitly required to not use T-SQL syntax. The application we are using supports T-SQL but we are not allowed to use it to avoid potential migration issues.
My question is: is the SELECT ... INTO statement T-SQL or SQL? If it is T-SQL, is there a specific SQL query to copy an existing table into a new one? (I have tried with CREATE TABLE AS .. FROM but it doesn't work).
Sounds like a very basic question but I haven't been able to find the answer anywhere. Thus, in addition to the question above, it would be very helpful to know if there is a guide/dictionary/website that collects only the standard SQL syntax.
Thanks!
I think they recommend you to use ANSI SQL, instead of T-SQL (SQL Server) or PL-SQL (ORACLE). Considering it as common requirement, every database vendor provide their own way of implementing this requirement. When you use ANSI SQL, you will not have migration issues, when you move from one database vendor to another database vendor.
SQL SERVER
SELECT * INTO new_table
FROM existing_table
ORACLE & ANSI-SQL
CREATE TABLE new_table
AS SELECT * FROM existing_table
is SELECT INTO TSQL or SQL?
Neither. The MySQL documentation claims that SELECT INTO is a Sybase extension to standard sql. As such I don't think you can accurately say it's either of these, but you can say that it's neither. It is indeed used in T-SQL, as well as some other database vendor products, to create a table from a query. The SQL standard says that queries with that goal should be formed as CREATE TABLE blah AS SELECT .... Oracle/MySQL, for example, use the standard form though you can see them use SELECT INTO in a different context, to assign data to variables in stored procedures
If you want to avoid use of this non standard syntax when creating and populating a table then you'll have to:
CREATE TABLE blah (column spec to match query output)
INSERT blah (select query here)
But then you run into nuances like "sqlserver calls it datetime/datetime2 but oracle calls it date/timestamp"
And ultimately you'll probably get into a situation where you just can't use one form of sql to do all you want..
I'd imagine most libraries that do data access on multiple underlying databases have mechanisms to use vendor specific terminology where required
From the answers, it appears you might need to specify which SELECT INTO you're talking about. The other answers seem to suggest there exists some kind of SELECT ... INTO <table-name> when there is also a kind of SELECT ... INTO <local-variable-name list>. The latter is used in embedded SQL for making SQL interact with variables of the host language program. I'm not certain but that variant may also be used in the part of the SQL language that deals with procedures written in SQL (the SQL/PSM part of the standard).
A "reference" that covers "only the standard SQL syntax" is, in principle, the ISO standard document itself, only available by purchase from ISO (and yes, it's ISO not ANSI - ANSI does nothing more than rubberstamping the ISO document after removing all the names of non-US contributors). And not the easiest kind of literature. There are "draft" versions floating around on the internet that might deviate from the published final standards. E.g. http://www.wiscorp.com/sql200n.zip. Note that this is a SQL:2008 draft. Current standard version is SQL:2011. And it's several thousands of pages, so I guess that covers your question "Is all the syntax covered in w3schools standard SQL". (Hint : no)
In SQL Server Compact Edition in Visual Studio 2010 (maybe SQL Server and SQL in general, I don't know), this command works:
DELETE FROM foods WHERE (name IN ('chickens', 'rabbits'))
but this command produces an error of: Error near identifier f. Expecting OUTPUT.
DELETE FROM foods f WHERE (f.name IN ('chickens', 'rabbits'))
To alias the table you'd have to say:
DELETE f FROM dbo.foods AS f WHERE f.name IN (...);
...though I fail to see the point of aliasing for this specific statement, especially since (at least IIRC) this no longer conforms to strict ANSI, may cause unnecessary hurdles when writing for multiple platforms, and it introduces complexity and confusion for new users learning the basics of vanilla DML.
This will do and doesn't require an alias:
DELETE dbo.foods WHERE name IN (...);
But yes, as comments suggest, it may be necessary for other query forms (e.g. any DML combined with correlation, joins, EXISTS, etc). In SQL Server you can do this using, for example:
DELETE f
FROM dbo.foods AS f
INNER JOIN dbo.allergies AS a
ON f.FoodId = a.FoodId;
Just keep in mind this query may have to be constructed differently on {not SQL Server}.
The delete statement has strange syntax. It goes like this:
DELETE f FROM foods f WHERE (f.name IN ('chickens', 'rabbits'))
I have a SqlServer db that I would like to port to MySQL. What's the best way to to this. Things that need to be ported are:
Tables (and data)
FileStream → MySQL equivalent?
Stored Procedures
Functions
Data types are relatively similar.
There is no equivalent to FileStream in MySQL - the files must either be stored as BLOBs, or on the file system while the path is stored in the database.
Migrating away from TSQL means:
There's no WITH clause in MySQL - it will have to converted into a derived table/inline view
There's no TOP syntax - these have to be converted to use LIMIT
There's no ranking/analytic functionality in MySQL - can't use ROW_NUMBER, RANK, DENSE_RANK or NTILE. See this article for alternatives.
MySQL views have notoriously limited functionality:
The SELECT statement cannot contain a subquery in the FROM clause.
The SELECT statement cannot refer to system or user variables.
Within a stored program, the definition cannot refer to program parameters or local variables.
The SELECT statement cannot refer to prepared statement parameters.
Any table or view referred to in the definition must exist. However, after a view has been created, it is possible to drop a table or view that the definition refers to. In this case, use of the view results in an error. To check a view definition for problems of this kind, use the CHECK TABLE statement.
The definition cannot refer to a TEMPORARY table, and you cannot create a TEMPORARY view.
Any tables named in the view definition must exist at definition time.
You cannot associate a trigger with a view.
As of MySQL 5.0.52, aliases for column names in the SELECT statement are checked against the maximum column length of 64 characters (not the maximum alias length of 256 characters).
Dynamic SQL will have to be converted to use MySQL's Prepared Statement syntax
A guide/article with some useful tips is available on the official MySQL dev site.
This is not for the faint of heart. Here is an article that explains what you are in for:
http://searchenterpriselinux.techtarget.com/news/column/0,294698,sid39_gci1187176,00.html
I'm trying to update all records in one table with the values found in another table.
I've tried many versions of the same basic query and always get the same error message:
Operation must use an updateable
query.
Any thoughts on why this query won't work in Access DB?
UPDATE inventoryDetails as idet
SET idet.itemDesc =
(
SELECT bomItemDesc
FROM BOM_TEMPLATES as bt
WHERE bt.bomModelNumber = idet.modelNumber
)
also tried this because I realized that since the second table has multiple model number records for each modelnumber - and I only need the first description from the first record found for each model number.
UPDATE inventoryDetails as idet
SET idet.item_desc =
(
SELECT TOP 1 bomItemDescription
FROM BOM_TEMPLATES as bt
WHERE bt.bomModelNumber = idet.modelNumber
)
...still getting the same error though.
You have to use a join
UPDATE inventoryDetails
INNER JOIN BOM_TEMPLATES ON inventoryDetails.modelNumber = BOM_TEMPLATES.bomModelNumber
SET inventoryDetails.itemDesc = [bomItemDesc];
Any thoughts on why this query won't work in Access DB?
The answer is, because ACE/Jet SQL syntax is not SQL-92 compliant (even when in its ANSI-92 Query Mode!).
I'm assuming yours is a scalar subquery. This construct is simply not supported by ACE/Jet.
ACE/Jet has its own quirky and flawed UPDATE..JOIN syntax, flawed because the engine doesn't force the JOINed values to be scalar and it is free to silently use an arbitrary value. It is different again from SQL Server's own UPDATE..JOIN syntax but at least SQL Server supports the Standard scalar subquery as an alternative. ACE/Jet forces you to either learn its quirky non-portable ways or to use an alternative SQL product.
Sorry to sound negative: the ACE/Jet engine is a great piece of software but UPDATE syntax is absolutely fundamental and the fact it hasn't been changed since the SQL-92 Standard really show its age.
try:
update idet
SET idet.itemDesc = bt.bomItemDesc
from inventoryDetails as idet
inner join BOM_TEMPLATES as bt
on bt.bomModelNumber = idet.modelNumber
This is how I would write it for SQL server. Hope Access understands the same command.