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SET versus SELECT when assigning variables?

What are the differences between the SET and SELECT statements when assigning variables in T-SQL? 4 Answers ...
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quick random row selection in Postgres

... You might want to experiment with OFFSET, as in SELECT myid FROM mytable OFFSET floor(random()*N) LIMIT 1; The N is the number of rows in mytable. You may need to first do a SELECT COUNT(*) to figure out the value of N. Update (by Antony Hatchkins) You must use floor he...
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SQL WHERE.. IN clause multiple columns

...a derived table from the subquery, and join table1 to this derived table: select * from table1 LEFT JOIN ( Select CM_PLAN_ID, Individual_ID From CRM_VCM_CURRENT_LEAD_STATUS Where Lead_Key = :_Lead_Key ) table2 ON table1.CM_PLAN_ID=table2.CM_PLAN_ID AND table1.Individual=table2.Indi...
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SQL/mysql - Select distinct/UNIQUE but return all columns?

... You're looking for a group by: select * from table group by field1 Which can occasionally be written with a distinct on statement: select distinct on field1 * from table On most platforms, however, neither of the above will work because the behavior o...
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SQL exclude a column using SELECT * [except columnA] FROM tableA?

We all know that to select all columns from a table, we can use 41 Answers 41 ...
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select * vs select column

If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory? ...
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How to get multiple counts with one SQL query?

...tion. This is basically the same thing as a PIVOT function in some RDBMS: SELECT distributor_id, count(*) AS total, sum(case when level = 'exec' then 1 else 0 end) AS ExecCount, sum(case when level = 'personal' then 1 else 0 end) AS PersonalCount FROM yourtable GROUP BY distributor_id ...
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How to select records from last 24 hours using SQL?

... SELECT * FROM table_name WHERE table_name.the_date > DATE_SUB(CURDATE(), INTERVAL 1 DAY) share | improve this answer ...
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MySQL INNER JOIN select only one row from second table

...have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL statements before so I want to know what i'm doing wrong. Appreciate the help ...
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MySQL select 10 random rows from 600K rows fast

How can I best write a query that selects 10 rows randomly from a total of 600k? 26 Answers ...
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