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How to find all the tables in MySQL with specific column names in them?
...rent column names that I want to look up in the entire DB and list out all tables which have those columns. Any easy script?
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What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
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Another point is that if table1 .a contains NULL the EXISTS query will not return this row but the NOT IN query will if table2 is empty. NOT IN vs. NOT EXISTS Nullable Columns: SQL Server
– Martin Smith
Jun 19 '...
How to join (merge) data frames (inner, outer, left, right)
...f performance is a major issue for you, you should also look into the data.table package - that's a whole new set of join syntax, but it's radically faster than anything we're talking about here.
– Matt Parker
Feb 12 '13 at 16:22
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SET versus SELECT when assigning variables?
... @var varchar(20)
set @var = 'Joe'
set @var = (select name from master.sys.tables where name = 'qwerty')
select @var /* @var is now NULL */
set @var = 'Joe'
select @var = name from master.sys.tables where name = 'qwerty'
select @var /* @var is still equal to 'Joe' */
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Throw an error in a MySQL trigger
If I have a trigger before the update on a table, how can I throw an error that prevents the update on that table?
7 An...
Generate GUID in MySQL for existing Data?
I've just imported a bunch of data to a MySQL table and I have a column "GUID" that I want to basically fill down all existing rows with new and unique random GUID's.
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Is the LIKE operator case-sensitive with MSSQL Server?
...al_cp1_cs_as
(d) To create a column using a different collation
create table exampletable (
examplecolumn varchar(10) collate sql_latin1_general_cp1_ci_as null
)
(e) To modify a column collation
alter table exampletable
alter column examplecolumn varchar(10) collate sql_latin1_general_cp1...
Oracle query to fetch column names
I have a mySQL query to get columns from a table like this:
12 Answers
12
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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...
Insert all values of a table into another table in SQL
I am trying to insert all values of one table into another. But the insert statement accepts values, but i would like it to accept a select * from the initial_Table. Is this possible?
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