Case 1 : Yes, this works fine.

Case 2 : This will fail with the error ORA-01441 : cannot decrease column length because some value is too big.

Share and enjoy.

Let&#39;s say I have

    type Person struct {
      Name string
    }
    func (p *Person) Label() string {
      return &quot;This is &quot; + p.Name
    }

How can I use this method from a html/template ? I would need something like this in my template:

    {{ .Label() }}


Call a method from a Go template

I&#39;m currently creating an iPhone app (Xcode 4.3.1, IOS 5) that could use Bluetooth devices! Main goal of this application is indoor navigation (GPS inside buildings isn&#39;t really accurate).

The only solution I see here (to keep my app on AppStore) is to try scan for available bluetooth devices!

I tried to use CoreBluetooth framework, but I don&#39;t get list of available devices! 
Maybe I don&#39;t use these functions correctly


    #import &lt;UIKit/UIKit.h&gt;
    #import &lt;CoreBluetooth/CoreBluetooth.h&gt;
    
    @interface AboutBhyperView : UIViewController &lt;CBPeripheralDelegate, CBCentralManagerDelegate&gt;
    {
        CBCentralManager *mgr;
    }
    @property (readwrite, nonatomic) CBCentralManager *mgr;
    @end
    
    
    
    - (void)viewDidLoad
    {
        [super viewDidLoad];
    
        mgr = [[CBCentralManager alloc] initWithDelegate:self queue:nil];
    }
    
    
    - (void)centralManager:(CBCentralManager *)central didDiscoverPeripheral:(CBPeripheral *)peripheral advertisementData:(NSDictionary *)advertisementData RSSI:(NSNumber *)RSSI {
       
       
        NSLog([NSString stringWithFormat:@&quot;%@&quot;,[advertisementData description]]);
    }
    
    -(void)centralManager:(CBCentralManager *)central didRetrievePeripherals:(NSArray *)peripherals{
        NSLog(@&quot;This is it!&quot;);
    }
    
    
    - (void)centralManagerDidUpdateState:(CBCentralManager *)central{ 
        NSString *messtoshow;
       
        switch (central.state) {
            case CBCentralManagerStateUnknown:
            {
                messtoshow=[NSString stringWithFormat:@&quot;State unknown, update imminent.&quot;];
                break;
            }
            case CBCentralManagerStateResetting:
            {
                messtoshow=[NSString stringWithFormat:@&quot;The connection with the system service was momentarily lost, update imminent.&quot;];
                break;
            }
            case CBCentralManagerStateUnsupported:
            {
                messtoshow=[NSString stringWithFormat:@&quot;The platform doesn&#39;t support Bluetooth Low Energy&quot;];
                break;
            }
            case CBCentralManagerStateUnauthorized:
            {
                messtoshow=[NSString stringWithFormat:@&quot;The app is not authorized to use Bluetooth Low Energy&quot;];
                break;
            }
            case CBCentralManagerStatePoweredOff:
            {
                messtoshow=[NSString stringWithFormat:@&quot;Bluetooth is currently powered off.&quot;];
                break;
            }
            case CBCentralManagerStatePoweredOn:
            {
                messtoshow=[NSString stringWithFormat:@&quot;Bluetooth is currently powered on and available to use.&quot;];
                [mgr scanForPeripheralsWithServices:nil options:nil];
                //[mgr retrieveConnectedPeripherals];
    
    //--- it works, I Do get in this area!

                break;
            }   
    
        }
        NSLog(messtoshow); 
    } 


I&#39;m not sure about this line, how to pass correct parameters?

    [mgr scanForPeripheralsWithServices:nil options:nil];

I took a look into apple reference .. and I still don&#39;t understand what&#39;s that CBUUID ???
Every device has some bluetooth id? where can I find it?

    - (void)scanForPeripheralsWithServices:(NSArray *)serviceUUIDs options:(NSDictionary *)options;

Parameters
serviceUUIDs - An array of CBUUIDs the app is interested in. 
options - A dictionary to customize the scan, see CBCentralManagerScanOptionAllowDuplicatesKey.


Is there any other way to use Bluetooth on IOS? I mean, older frameworks that don&#39;t use BLE 4.0!


any advice would be appreciated!

thanks!



How to get list of available Bluetooth devices?

&gt; **Possible Duplicate:**  
&gt; [How to make a varchar2 field shorter in Oracle?](https://stackoverflow.com/questions/8404194/how-to-make-a-varchar2-field-shorter-in-oracle)  

&lt;!-- End of automatically inserted text --&gt;

In Oracle(9i and above)

     Alter table employee  
     MODIFY ename varchar2(10);

I want to alter the column ename of table employee from varchar2(30) to varchar2(10)
  
 - Case1 : if the table has data having ename column containing values which are of length less than 10 char(i mean it can fit in varchar2(10) comfortably) - is this allowed by oracle ?

 - Case 2: if the table has data having ename column containing values which are of length greater than 10 char(i mean it can not fit in varchar2(10)) - is this not allowed by oracle ?

alter the size of column in table containing data

> Possible Duplicate: 
> <a href="https://stackoverflow.com/questions/8404194/how-to-make-a-varchar2-field-shorter-in-oracle" target="_blank" rel="noopener noreferrer">How to make a varchar2 field shorter in Oracle?</a>

In Oracle(9i and above)
<pre><code class="hljs language-scss"> Alter table employee 
 MODIFY ename varchar2(10);
</code></pre>
I want to alter the column ename of table employee from varchar2(30) to varchar2(10)
<ul>
<li>
Case1 : if the table has data having ename column containing values which are of length less than 10 char(i mean it can fit in varchar2(10) comfortably) - is this allowed by oracle ?
</li>
<li>
Case 2: if the table has data having ename column containing values which are of length greater than 10 char(i mean it can not fit in varchar2(10)) - is this not allowed by oracle ?
</li>
</ul>

I&#39;m trying to join 3 tables in a view; here is the situation:

I have a table that contains information of students who are applying to live on this College Campus. I have another table that lists the Hall Preferences (3 of them) for each Student. But each of these preferences are merely an ID Number, and the ID Number has a corresponding Hall Name in a third table (did not design this database...).

Pretty much, I have `INNER JOIN` on the table with their preferences, and their information, the result is something like...

     John Doe | 923423 | Incoming Student | 005

Where `005` would be the `HallID`. So Now I want to match that `HallID` to a third table, where this table contains a `HallID` and `HallName`.

So pretty much, I want my result to be like...

     John Doe | 923423 | Incoming Student | Foley Hall &lt;---(INSTEAD OF 005)

Here is what I currently have:

    SELECT
      s.StudentID, s.FName, 
      s.LName, s.Gender, s.BirthDate, s.Email, 
      r.HallPref1, r.HallPref2, r.HallPref3
    FROM
      dbo.StudentSignUp AS s 
      INNER JOIN RoomSignUp.dbo.Incoming_Applications_Current AS r 
        ON s.StudentID = r.StudentID 
      INNER JOIN HallData.dbo.Halls AS h 
        ON r.HallPref1 = h.HallID

SQL Inner-join with 3 tables?

I have this, and i get an error at set total.
Why can&#39;t i access a cte many times?

    ALTER PROCEDURE [dbo].[GetLeaguePlayers]
    (
    	@idleague int,
    	@pageNumber int,
    	@pageSize int,
    	@total int OUTPUT
    )
    AS
    WITH CTEPlayers AS
    (
    	SELECT ROW_NUMBER() OVER (ORDER BY p.Name) AS RowNumber, p.Id, p.Name, t.Name AS Team
    	FROM Players p INNER JOIN Teams t ON p.IdTeam=t.Id INNER JOIN Leagues l ON l.Id=t.IdLeague
    	WHERE l.Id=@idleague
    )
    SELECT Id, Name
    FROM CTEPlayers c
    WHERE RowNumber&gt;@pageSize*(@pageNumber-1) AND RowNumber&lt;@pageSize*@pageNumber;
    SET @total = ( SELECT COUNT(*) FROM CTEPlayers )

Use one CTE many times

I have a table that has 20 integer columns and 1 text column named &#39;foo&#39;

If I run query:

    SELECT * from table_name where foo is NULL

I get error:

    ERROR:  column &quot;foo&quot; does not exist

I have checked myself that his column indeed exists. If I do something like:

    SELECT * from table_name where count is NULL

The resulting output shows &#39;foo&#39; as one of the columns....
I am guessing I have to do something special in the query because foo is a text column...

Thanks for the help (POSTGRESQL 8.3)

PostgreSQL column &#39;foo&#39; does not exist

Is there an SQL instruction to retrieve the value of a sequence that does not increment it.

Thanks.

**EDIT AND CONCLUSION** 

As stated by Justin Cave It&#39;s not useful to try to &quot;save&quot; sequence number so


    select a_seq.nextval from dual;

is good enough to check a sequence value.

I still keep Ollie answer as the good one because it answered the initial question. but ask yourself about the necessity of not modifying the sequence if you ever want to do it.



How to retrieve the current value of an oracle sequence without increment it?

How can I discard/round the `millisecond` part, better if the `second` part is also removed from a `timestamp` w/o `timezone` ?

Discard millisecond part from timestamp

I am referring to this `stackoverflow` answer:

https://stackoverflow.com/questions/1564956/how-can-i-select-from-list-of-values-in-sql-server/7285095#7285095

How could something similar be done in **Oracle**?

I&#39;ve seen the other answers on this page that use `UNION` and although this method technically works, it&#39;s not what I would like to use in my case.

So I would like to stay with syntax that more or less looks like a comma-separated list of values.

**UPDATE** *regarding the `create type table` [answer][1]*:

I have a table:

    CREATE TABLE BOOK
    (	&quot;BOOK_ID&quot; NUMBER(38,0)
    )

I use this script but it does not insert any rows to the `BOOK` table:

    create type number_tab is table of number;
    
    INSERT INTO BOOK (
        BOOK_ID
    )
    SELECT A.NOTEBOOK_ID FROM
        (select column_value AS NOTEBOOK_ID from table (number_tab(1,2,3,4,5,6))) A
    ;

Script output:

    TYPE number_tab compiled
    Warning: execution completed with warning

But if I use this script it does insert new rows to the `BOOK` table:

    INSERT INTO BOOK (
        BOOK_ID
    )
    SELECT A.NOTEBOOK_ID FROM
        (SELECT (LEVEL-1)+1 AS NOTEBOOK_ID FROM DUAL CONNECT BY LEVEL&lt;=6) A
    ;


  [1]: https://stackoverflow.com/questions/10353969/how-can-i-select-from-list-of-values-in-oracle/10354083#10354083

How can I select from list of values in Oracle

I am writing a Java app to export data from Oracle to csv file

Unfortunately the content of data may quite tricky. Still comma is the deliminator, but some data on a row could be like this:

    | ID    |   FN    |   LN   |  AGE   |  COMMENT                   |
    |----------------------------------------------------------------|
    | 123   |  John   |  Smith |   39   | I said &quot;Hey, I am 5&#39;10&quot;.&quot;  |
    |----------------------------------------------------------------|

so this is one of the string on the `comment` column:

&gt;I said &quot;Hey, I am 5&#39;10&quot;.&quot;

No kidding, I need to show above comment without compromise in excel or open office from a CSV file generated by Java, and of course cannot mess up other regular escaping situation(i.e. regular double quotes, and regular comma within a tuple). I know regular expression is powerful but how can we achieve the goal with such complicated situation?


How to escape comma and double quote at same time for CSV file?

i created a sequence using the following query,

    create sequence qname_id_seq start with 1 increment by 1 nocache;

Now when i try to create a table which uses the above sequence, it is throwing the following error,

    Error report:
    SQL Error: ORA-00907: missing right parenthesis
    00907. 00000 -  &quot;missing right parenthesis&quot;

I used the following query to create a table with sequence.nextval,

    CREATE TABLE qname
    (
        qname_id integer NOT NULL default qname_id_seq.nextval PRIMARY KEY,
        qname    VARCHAR2(4000) NOT NULL -- CONSTRAINT qname_uk UNIQUE
    );

create table with sequence.nextval in oracle

I have a simple test program that when I run I get:

    ./hello: error while loading shared libraries: libaio.so.1: cannot open shared object file: No such file or directory

I link it like this:

    $(CC) $(CCFLAGS) -o hello hello.o -L../ocilib-3.9.3/src/.libs -L../instantclient_11_2 -locilib

My LD_LIBRARY_PATH contains this:

    LD_LIBRARY_PATH=../ocilib-3.9.3/src/.libs:../instantclient_11_2:/usr/lib

/usr/lib looks like this:

    Linux$ ls -l /usr/lib/libaio*
    lrwxrwxrwx  1 root root   15 Nov  5  2008 /usr/lib/libaio.so.1 -&gt; libaio.so.1.0.1
    -rwxr-xr-x  1 root root 2632 Sep 16  2005 /usr/lib/libaio.so.1.0.0
    -rwxr-xr-x  1 root root 2628 Sep 16  2005 /usr/lib/libaio.so.1.0.1

Output of ldd hello:

    libocilib.so.3 =&gt; ../ocilib-3.9.3/src/.libs/libocilib.so.3 (0x0000002a95558000)
    libc.so.6 =&gt; /lib64/tls/libc.so.6 (0x0000003811200000)
    libclntsh.so.11.1 =&gt; ../instantclient_11_2/libclntsh.so.11.1 (0x0000002a956c4000)
    /lib64/ld-linux-x86-64.so.2 (0x000000552aaaa000)
    libnnz11.so =&gt; ../instantclient_11_2/libnnz11.so (0x0000002a97f56000)
    libdl.so.2 =&gt; /lib64/libdl.so.2 (0x0000003811500000)
    libm.so.6 =&gt; /lib64/tls/libm.so.6 (0x0000003811700000)
    libpthread.so.0 =&gt; /lib64/tls/libpthread.so.0 (0x0000003811b00000)
    libnsl.so.1 =&gt; /lib64/libnsl.so.1 (0x0000003819000000)
    libaio.so.1 =&gt; not found

I&#39;m hoping that I&#39;m missing something simple here.  The oracle instantclient package appears to require libaio, but that seems to be installed already so what&#39;s the problem?


Content Type	Original Author	Original Content on Stackoverflow
Question	lowLatency	View Question on Stackoverflow
Solution 1 - Sql	Bob Jarvis - Слава Україні	View Answer on Stackoverflow

alter the size of column in table containing data

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How to get list of available Bluetooth devices?

Call a method from a Go template

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