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Error renaming a column in MySQL
How do I rename a column in table xyz ? The columns are:
9 Answers
9
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How do I check in SQLite whether a table exists?
How do I, reliably , check in SQLite, whether a particular user table exists?
22 Answers
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Rails: Using build with a has_one association in rails
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Supposedly if user belonged to profile(meaning user table has foreign_key profile_id in its table) then also building profile for user will work as mentioned above i.e but for new action only user.build_profile for edit user.build_profile if user.profile.nil? and if you w...
How do I restore a dump file from mysqldump?
...mmand prompt (in Windows) and cd to the directory where the mysql.exe executable is (you may have to look around a bit for it, it'll depend on how you installed mysql, i.e. standalone or as part of a package like WAMP). Once you're in that directory, you should be able to just type the command as I...
Delete duplicate records in SQL Server?
Consider a column named EmployeeName table Employee . The goal is to delete repeated records, based on the EmployeeName field.
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How to Vertical align elements in a div?
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This also works with inline-block and table-cell elements. If you are having issues with this, try adjusting line-height of the container element (i.e. context) since it is used in the vertical-align line box calculations.
– Alex W
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INNER JOIN vs LEFT JOIN performance in SQL Server
I've created SQL command that uses INNER JOIN on 9 tables, anyway this command takes a very long time (more than five minutes). So my folk suggested me to change INNER JOIN to LEFT JOIN because the performance of LEFT JOIN is better, despite what I know. After I changed it, the speed of query got si...
How to take MySQL database backup using MySQL Workbench?
...different way as given below-
Q.1) Backup file(.sql) contains both Create Table statements and Insert into Table Statements
ANS:
Select Start Export Option
Q.2) Backup file(.sql) contains only Create Table Statements, not Insert into Table statements for all tables
ANS:
Select Skip Table Da...
SQL variable to hold list of integers
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Table variable
declare @listOfIDs table (id int);
insert @listOfIDs(id) values(1),(2),(3);
select *
from TabA
where TabA.ID in (select id from @listOfIDs)
or
declare @listOfIDs varchar(1000);
SET @listOfIDs = ',1,2,3...
Bash empty array expansion with `set -u`
...-} or ${arr[@]:0}, are not safe across all major versions of Bash.
As the table below shows, the only expansion that is reliable across all modern-ish Bash versions is ${arr[@]+"${arr[@]}"} (column +"). Of note, several other expansions fail in Bash 4.2, including (unfortunately) the shorter ${arr[...