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SQL Server reports 'Invalid column name', but the column is present and the query works through mana
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I suspect that you have two tables with the same name. One is owned by the schema 'dbo' (dbo.PerfDiag), and the other is owned by the default schema of the account used to connect to SQL Server (something like userid.PerfDiag).
When you have an unquali...
Is there any boolean type in Oracle databases?
...efer char(1) because it uses less space. You can check it this way: create table testbool (boolc char(1), booln number(1)); insert into testbool values ('Y', 1 ); select dump(boolc), dump(booln) from testbool; That CHAR is stored: Typ=96 Len=1: 89 and that NUMBER: Typ=2 Len=2: 193,2 At least in 12c...
Display / print all rows of a tibble (tbl_df)
...ated by the dplyr data frame manipulation package in R. It prevents long table outputs when accidentally calling the data frame.
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IN clause and placeholders
...", "name2" }; // do whatever is needed first
String query = "SELECT * FROM table"
+ " WHERE name IN (" + makePlaceholders(names.length) + ")";
Cursor cursor = mDb.rawQuery(query, names);
Just make sure to pass exactly as many values as places. The default maximum limit of host parameters in SQ...
How do I escape a single quote in SQL Server?
I'm trying to insert some text data into a table in SQL Server 9.
13 Answers
13
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Remove all spaces from a string in SQL Server
... trim() or worry about multiple spaces for either char or varchar:
create table #t (
c char(8),
v varchar(8))
insert #t (c, v) values
('a a' , 'a a' ),
('a a ' , 'a a ' ),
(' a a' , ' a a' ),
(' a a ', ' a a ')
select
'"' + c + '"' [IN], '"' + replac...
For loop example in MySQL
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drop table if exists foo;
create table foo
(
id int unsigned not null auto_increment primary key,
val smallint unsigned not null default 0
)
engine=innodb;
drop procedure if exists load_foo_test_data;
delimiter #
create procedur...
How to prepend a string to a column value in MySQL?
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UPDATE tablename SET fieldname = CONCAT("test", fieldname) [WHERE ...]
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How to generate an entity-relationship (ER) diagram using Oracle SQL Developer
I want to use Oracle SQL Developer to generate an ER diagram for my DB tables but I am new to Oracle and this tool.
8 Answe...
What good are SQL Server schemas?
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Schemas logically group tables, procedures, views together. All employee-related objects in the employee schema, etc.
You can also give permissions to just one schema, so that users can only see the schema they have access to and nothing else.
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