i have a DB which has a table named LIKE.
uppon trying to execute any query on the table, it gives me an error and i know it's because of the name which is trying to use the query keyword LIKE.
Now, i have "bypassed" this issue in MySQL by just selecting the table as
SELECT tk_oseba_id, COUNT(tk_tip_like_id) AS St_Like_haha
FROM student999.`like`;
Now this same line wont work at `l...is there any special way to to this in oracle or how can i manipulate with the table by not using the LIKE keyword.
Oracles's counter part to mysql's back tick is quote for defining tablenames/columns.
To use a key word as a table name though I recommend against it...
wrap the table name in quotes. From student9999."like"
AND... it forces case sensitivity when you use the quotes!
One of my columns is called from. I can't change the name because I didn't make it.
Am I allowed to do something like SELECT from FROM TableName or is there a special syntax to avoid the SQL Server being confused?
Wrap the column name in brackets like so, from becomes [from].
select [from] from table;
It is also possible to use the following (useful when querying multiple tables):
select table.[from] from table;
If it had been in PostgreSQL, use double quotes around the name, like:
select "from" from "table";
Note: Internally PostgreSQL automatically converts all unquoted commands and parameters to lower case. That have the effect that commands and identifiers aren't case sensitive. sEleCt * from tAblE; is interpreted as select * from table;. However, parameters inside double quotes are used as is, and therefore ARE case sensitive: select * from "table"; and select * from "Table"; gets the result from two different tables.
These are the two ways to do it:
Use back quote as here:
SELECT `from` FROM TableName
You can mention with table name as:
SELECT TableName.from FROM TableName
While you are doing it - alias it as something else (or better yet, use a view or an SP and deprecate the old direct access method).
SELECT [from] AS TransferFrom -- Or something else more suitable
FROM TableName
Your question seems to be well answered here, but I just want to add one more comment to this subject.
Those designing the database should be well aware of the reserved keywords and avoid using them. If you discover someone using it, inform them about it (in a polite way). The keyword here is reserved word.
More information:
"Reserved keywords should not be used
as object names. Databases upgraded
from earlier versions of SQL Server
may contain identifiers that include
words not reserved in the earlier
version, but that are reserved words
for the current version of SQL Server.
You can refer to the object by using
delimited identifiers until the name
can be changed."
http://msdn.microsoft.com/en-us/library/ms176027.aspx
and
"If your database does contain names
that match reserved keywords, you must
use delimited identifiers when you
refer to those objects. For more
information, see Identifiers (DMX)."
http://msdn.microsoft.com/en-us/library/ms132178.aspx
In Apache Drill, use backquotes:
select `from` from table;
If you ARE using SQL Server, you can just simply wrap the square brackets around the column or table name.
select [select]
from [table]
I have also faced this issue.
And the solution for this is to put [Column_Name] like this in the query.
string query= "Select [Name],[Email] from Person";
So it will work perfectly well.
Hi I work on Teradata systems that is completely ANSI compliant. Use double quotes " " to name such columns.
E.g. type is a SQL reserved keyword, and when used within quotes, type is treated as a user specified name.
See below code example:
CREATE TABLE alpha1
AS
(
SEL
product1
type_of_product AS "type"
FROM beta1
) WITH DATA
PRIMARY INDEX (product1)
--type is a SQL reserved keyword
TYPE
--see? now to retrieve the column you would use:
SEL "type" FROM alpha1
I ran in the same issue when trying to update a column which name was a keyword. The solution above didn't help me. I solved it out by simply specifying the name of the table like this:
UPDATE `survey`
SET survey.values='yes,no'
WHERE (question='Did you agree?')
The following will work perfectly:
SELECT DISTINCT table.from AS a FROM table
Some solid answers—but the most-upvoted one is parochial, only dealing with SQL Server. In summary:
If you have source control, the best solution is to stick to the rules, and avoid using reserved words. This list has been around for ages, and covers most of the peculiarities. One tip is that reserved words are rarely plural—so you're usually safe using plural names. Exceptions are DIAGNOSTICS, SCHEMAS, OCTETS, OFFSETS, OPTIONS, VALUES, PARAMETERS, PRIVILEGES and also verb-like words that also appear plural: OVERLAPS, READS, RETURNS, TRANSFORMS.
Many of us don't have the luxury of changing the field names. There, you'll need to know the details of the RDBM you're accessing:
For SQL Server use [square_braces] around the name. This works in an ODBC connection too.
For MySQL use `back_ticks`.
Postgres, Oracle and several other RDBMs will apparently allow "double_quotes" to be used.
Dotting the offending word onto the table name may also work.
You can put your column name in bracket like:
Select [from] from < ur_tablename>
Or
Put in a temprary table then use as you like.
Example:
Declare #temp_table table(temp_from varchar(max))
Insert into #temp_table
Select * from your_tablename
Here I just assume that your_tablename contains only one column (i.e. from).
In MySQL, alternatively to using back quotes (`), you can use the UI to alter column names. Right click the table > Alter table > Edit the column name that contains sql keyword > Commit.
select [from] from <table>
As a note, the above does not work in MySQL
Judging from the answers here and my own experience. The only acceptable answer, if you're planning on being portable is don't use SQL keywords for table, column, or other names.
All these answers work in the various databases but apparently a lot don't support the ANSI solution.
Simple solution
Lets say the column name is from ; So the column name in query can be referred by table alias
Select * from user u where u.from="US"
In Oracle SQL Developer, pl/sql you can do this with double quotes but if you use double quotes you must type the column names in upper case. For example, SELECT "FROM" FROM MY_TABLE
We have a legacy application we cannot modify that connects to Oracle 11g and at some point runs a query and returns a result. The application however is using the "generated" column name from Oracle to read the result.
Consider the following query:
select nvl(1,0.0) from DUAL;
As this query does not specify an alias, the generated column name would be "nvl(1,0.0)"
However on another server the generated column name is "nvl(1,0)" (notice 0 and not 0.0) and the application fails.
Is there a configuration that can be changed for Oracle? I've searched for formatting and locale configurations and they are equal on both servers.
Any help would be appreciated
It turns out there's a parameter called cursor_sharing that was set to FORCE instead of EXACT
select nvl(1,0.0) from DUAL;
The query above returns the following depending on the value of the parameter:
FORCE=NVL(1,0)
EXACT=NVL(1,0.0)
I'm currently porting a Code Igniter based application from MySQL to Oracle (11g) for a specific client. Both the MySQL and Oracle back-ends have to work in conjunction (i.e. we cannot drop the one or the other).
The MySQL DB uses around 100 tables of which ALL identifiers are in lowercase. When I migrate this DB to Oracle, using Oracle's SQL Developer tool, I end up with a 'properly' converted DB, but... with all uppercase identifiers.
Now, for normal usage this isn't really a problem, but the issue arises when using the CI Active Record class. It generates queries to the effect of:
SELECT "somecolumn" FROM "sometable" WHERE "someothercolumn" = somevalue
The issue is that when the " quotes are used for these identifiers, Oracle forces these identifiers to be interpreted in a case sensitive way, which in this case is wreaking havoc.
Patching the core code of CI and/or the application to either make all queries use case insensitive identifiers (i.e. by dropping the usage of the " quotes around the identifiers) or to convert all identifiers to uppercase ones on the fly, is IMO not desired, as a potential future framework upgrade is then compromised. Renaming ALL MySQL identifiers to become in uppercase is also a very unattractive scenario and has an even bigger impact on the application itself -- not an option for sure.
Instead, what I would like to achieve, is to have the migration process (i.e. using SQL Developer) simply respecting the case of the source DB and to perform the conversion exactly as it does up to now, with the exception that the identifiers do not get changed to their uppercase version.
I have searched a fair deal online to find a way to achieve this, and so far it has been to no avail.
Does anyone know if this can be done, and if so: how?
Is the conversion to all uppercase identifiers by any chance a global DB setting, perhaps?
I would have assumed this to be a trivial thing, but I haven't been able to figure it out so far and what little related references that I did come across do not sound very promising...
If you can acquire a schema script created by the database migration all you need to do is change the identifiers ( tablenames, view names, column names etc ) to be surrounded with double quotation marks. (I'm not sure if SQL Developer migrations actually has the option to preserve the case).
Without the quote marks Oracle will assume all identifiers are case-insensitive. However this is stored internally as upper case strings in the data dictionary. By using quote marks will force Oracle to use the exact case for the schema objects.
eg.
create table Customers
(
Name varchar2(100),
CreationDate date not null
);
will create CUSTOMERS internally in the data-dictionar and you can write queries like:
select name, creationdate from customers;
alternatively:
create table "Customers"
(
"Name" varchar2(100),
"CreationDate" date not null
);
will create "Customers" internally. You can only write queries using quotes and exact case:
select "Name", "CreationDate" from "Customers";
I have hit this before and simply edited oci8_driver.php (../system/database/oci) as follows:
// The character used for excaping
var $_escape_char = '"';
to
// The character used for excaping
var $_escape_char = '';
Stewart
I have the linked server set up in SQL Server 2008. But I could not run any query against the linked server.
I tried to run this simple command but it's not working
SELECT * FROM MYSERVER..ALANH.TEMP_UPDATE1
This is the error I got when I run the above command.
Msg 7399, Level 16, State 1, Line 1
The OLE DB provider "OraOLEDB.Oracle" for linked server "MYSERVER" reported an error. The provider did not give any information about the error.
Msg 7312, Level 16, State 1, Line 1
Invalid use of schema or catalog for OLE DB provider "OraOLEDB.Oracle" for linked server "MYSERVER". A four-part name was supplied, but the provider does not expose the necessary interfaces to use a catalog or schema.
Could anyone help me to connect to the OracleLinkedServer? Thanks very much.
you can be that way too:
**SELECT * FROM OPENQUERY(MYSERVER, 'SELECT * FROM ALANH.TEMP_UPDATE1')**
You can write the query like this:
select * FROM [MYSERVER]..[ALANH].[TEMP_UPDATE1]
Important: In this case, the fully qualified table name must be written in upper case.
You might try the fix from this article.
Also, this could be a problem with naming. From an MS KB article
If you receive these error messages, a table may be missing in the
Oracle schema or you may not have permissions on that table. Verify
that the schema name has been typed by using uppercase. The
alphabetical case of the table and of the columns should be as
specified in the Oracle system tables.
On the Oracle side, a table or a column that is created without double
quotation marks is stored in uppercase. If the table or the column is
enclosed in double quotation marks, the table or the column is stored
as is.
First make sure the tnsping utility works from client server, then use the below string in linked server database source setup
host[:port]/service_name
Check this link for more details :
http://www.oracledistilled.com/oracle-database/oracle-net/using-easy-connect-ezconnect-naming-method-to-connect-to-oracle-databases/
Try something like this:
SELECT * FROM ALL_TABLES#"SOME.SERVER.NAME";
In this case I'm selecting ALL_TABLES from a linked server called SOME.SERVER.NAME.
Richard's post above was critical.
I am using v12 ODP.NET odbc drivers and had to ensure that "Zero Level Only" was NOT checked and that the names supplied for table and schema were the correct case. All of the schemas and tables I access are uppercase only.
Use the query below to determine what the correct table name is, though you will have to supply the schema name in the correct case for the query to work. Try all uppercase, try all lowercase, try mixed case, or better yet get the actual name from the dba (I've heard that only table/schema names that are "" quoted will be allowed mixed case, otherwise in oracle it's all uppercase.)
sp_tables_ex #table_server=InsertLinkedServerHere, #table_schema=InsertSchemaNameHere