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Get list of all tables in Oracle?

... SELECT owner, table_name FROM dba_tables This is assuming that you have access to the DBA_TABLES data dictionary view. If you do not have those privileges but need them, you can request that the DBA explicitly grants you...
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How to get a list of user accounts using the command line in MySQL?

... Use this query: SELECT User FROM mysql.user; Which will output a table like this: +-------+ | User | +-------+ | root | +-------+ | user2 | +-------+ As Matthew Scharley points out in the comments on this answer, you can group by the ...
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Get current AUTO_INCREMENT value for any table

...'TableName' ; You can get exactly this information by using this query: SELECT `AUTO_INCREMENT` FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = 'DatabaseName' AND TABLE_NAME = 'TableName'; share | ...
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mysql :: insert into table, data from another table?

... INSERT INTO action_2_members (campaign_id, mobile, vote, vote_date) SELECT campaign_id, from_number, received_msg, date_received FROM `received_txts` WHERE `campaign_id` = '8' share | imp...
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Rank function in MySQL

... One option is to use a ranking variable, such as the following: SELECT first_name, age, gender, @curRank := @curRank + 1 AS rank FROM person p, (SELECT @curRank := 0) r ORDER BY age; The (SELECT @curRank := 0) part allows the variable initializatio...
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How to count instances of character in SQL Column

... In SQL Server: SELECT LEN(REPLACE(myColumn, 'N', '')) FROM ... share | improve this answer | follow ...
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Extract a dplyr tbl column as a vector

...2 3.62 3.54 4.11 A nice way to do this in v0.2 of dplyr: iris2 %>% select(Species) %>% collect %>% .[[5]] Or if you prefer: iris2 %>% select(Species) %>% collect %>% .[["Species"]] Or if your table isn't too big, simply... iris2 %>% collect %>% .[["Species"]] ...
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SQL statement to get column type

... Using SQL Server: SELECT DATA_TYPE FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'yourTableName' AND COLUMN_NAME = 'yourColumnName' share |...
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LINQ - Full Outer Join

...rst.ID equals last.ID into temp from last in temp.DefaultIfEmpty() select new { first.ID, FirstName = first.Name, LastName = last?.Name, }; var rightOuterJoin = from last in lastNames join first in firstNames on last.ID equals first.ID into temp fr...
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SQLite - UPSERT *not* INSERT or REPLACE

... (id, role, name) VALUES ( 1, 'code monkey', (SELECT name FROM Employee WHERE id = 1) ); This will update 2 of the columns. When ID=1 exists, the ROLE will be unaffected. When ID=1 does not exist, the role will be set to 'Benchwarmer' instead of the default v...