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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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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...
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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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...
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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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...
How can I insert values into a table, using a subquery with more than one result?
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If you are inserting one record into your table, you can do
INSERT INTO yourTable
VALUES(value1, value2)
But since you want to insert more than one record, you can use a SELECT FROM in your SQL statement.
so you will want to do this:
INSERT INTO prices (group,...
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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How to implement the activity stream in a social network
...rowse far back in time (if you even offer this)
I use a plain old MySQL table for dealing with about 15 million activities.
It looks something like this:
id
user_id (int)
activity_type (tinyint)
source_id (int)
parent_id (int)
parent_type (tinyint)
time (...
Find all records which have a count of an association greater than zero
...s a matter of preference. The count can be done with any field in the join table that is guaranteed to have a value in every row. Most meaningful candidates are projects.id, project_id, and vacancies.id. I chose to count project_id because it is the field on which the join is made; the spine of the ...