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How to add new column to MYSQL table?
I am trying to add a new column to my MYSQL table using PHP. I am unsure how to alter my table so that the new column is created. In my assessment table I have:
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Postgres unique constraint vs index
... but important issue, so I decided to learn by example.
Let's create test table master with two columns, con_id with unique constraint and ind_id indexed by unique index.
create table master (
con_id integer unique,
ind_id integer
);
create unique index master_unique_idx on master (ind_id)...
Export specific rows from a PostgreSQL table as INSERT SQL script
I have a database schema named: nyummy and a table named cimory :
9 Answers
9
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Get all table names of a particular database by SQL query?
...nt sql dbms deal with schemas.
Try the following
For SQL Server:
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_CATALOG='dbName'
For MySQL:
SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE' AND TABLE_SCHEMA='dbName'
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How to add a primary key to a MySQL table?
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After adding the column, you can always add the primary key:
ALTER TABLE goods ADD PRIMARY KEY(id)
As to why your script wasn't working, you need to specify PRIMARY KEY, not just the word PRIMARY:
alter table goods add column `id` int(10) unsigned primary KEY AUTO_INCREMENT;
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Reset AutoIncrement in SQL Server after Delete
I've deleted some records from a table in a SQL Server database. Now the ID's go from 101 to 1200. I want to delete the records again, but I want the ID's to go back to 102. Is there a way to do this in SQL Server?
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How to change the default charset of a MySQL table?
There is a MySQL table which has this definition taken from SQLYog Enterprise :
5 Answers
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MySQL Creating tables with Foreign Keys giving errno: 150
I am trying to create a table in MySQL with two foreign keys, which reference the primary keys in 2 other tables, but I am getting an errno: 150 error and it will not create the table.
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How to DROP multiple columns with a single ALTER TABLE statement in SQL Server?
... like to write a single SQL command to drop multiple columns from a single table in one ALTER TABLE statement.
11 Answers...
PostgreSQL Autoincrement
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Yes, SERIAL is the equivalent function.
CREATE TABLE foo (
id SERIAL,
bar varchar);
INSERT INTO foo (bar) values ('blah');
INSERT INTO foo (bar) values ('blah');
SELECT * FROM foo;
1,blah
2,blah
SERIAL is just a create table time macro around sequences. You can not ...