PostgreSQL – SQL commands
List of some useful MySQL commands in SQL queries.
Resetting the increment:
ALTER TABLE market AUTO_INCREMENT = 1;
ALTER TABLE outcome AUTO_INCREMENT = 1;
ALTER TABLE outcome AUTO_INCREMENT = 1;
Add a new column (one command at a time):
ALTER TABLE table_name ADD post_date_gmt datetime NOT NULL DEFAULT ‘0000-00-00 00:00:00’
ALTER TABLE table_name ADD post_title text COLLATE utf8mb4_unicode_ci NOT NULL
ALTER TABLE table_name ADD post_content longtext COLLATE utf8mb4_unicode_ci NOT NULL
ALTER TABLE table_name ADD post_author bigint (20) unsigned NOT NULL DEFAULT ‘0’
ALTER TABLE table_name ADD post_title text COLLATE utf8mb4_unicode_ci NOT NULL
ALTER TABLE table_name ADD post_content longtext COLLATE utf8mb4_unicode_ci NOT NULL
ALTER TABLE table_name ADD post_author bigint (20) unsigned NOT NULL DEFAULT ‘0’
Rename Column:
ALTER TABLE table_name CHANGE post_date_gmt date_creation_gmt datetime NOT NULL DEFAULT ‘0000-00-00 00:00:00’;
ALTER TABLE table_name CHANGE post_title title text COLLATE utf8mb4_unicode_ci NOT NULL;
ALTER TABLE table_name CHANGE post_content content longtext COLLATE utf8mb4_unicode_ci NOT NULL;
ALTER TABLE table_name CHANGE post_author author_id bigint (20) unsigned NOT NULL DEFAULT ‘0’;
ALTER TABLE table_name CHANGE post_title title text COLLATE utf8mb4_unicode_ci NOT NULL;
ALTER TABLE table_name CHANGE post_content content longtext COLLATE utf8mb4_unicode_ci NOT NULL;
ALTER TABLE table_name CHANGE post_author author_id bigint (20) unsigned NOT NULL DEFAULT ‘0’;
Update specific values in a column:
UPDATE table_name SET category = REPLACE (category, ‘work’, ‘2’);
Update all values in a column:
UPDATE table_name SET category = 1;
Update empty data in the column with some other data, for example, number 1:
UPDATE table_name set category ="one" where category is null OR category =""
UPDATE table_name set user_id ="one"
Or
AND (t.status = “a” OR t.status = “b”)
Delete column:
ALTER TABLE actions DROP COLUMN name_ru;