大约有 47,000 项符合查询结果(耗时:0.0255秒) [XML]

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Search All Fields In All Tables For A Specific Value (Oracle)

...based on what I think it should be named but it returned no results.* SELECT * from dba_objects WHERE object_name like '%DTN%' A column isn't an object. If you mean that you expect the column name to be like '%DTN%', the query you want is: SELECT owner, table_name, column_name FROM all_tab...
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Saving enum from select in Rails 4.1

...num. I changed the input to be the following: f.input :color, :as => :select, :collection => Wine.colors.keys.to_a Which generated the following HTML: <select id="wine_color" name="wine[color]"> <option value=""></option> <option value="red">red</option> ...
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How do I use ROW_NUMBER()?

... For the first question, why not just use? SELECT COUNT(*) FROM myTable to get the count. And for the second question, the primary key of the row is what should be used to identify a particular row. Don't try and use the row number for that. If you returned Ro...
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What is the difference D3 datum vs. data?

...rs here on SO are not complete as they only cover the case when you invoke selection.data and selection.datum with an input data parameter. Even in that scenario, the two behave differently if the selection is a single element versus when it contains multiple elements. Moreover, both of these method...
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How to search a specific value in all tables (PostgreSQL)?

... If you're using IntelliJ you can just right-click your db and select "Dump with 'pg_dump'" or "Dump data to file(s)" – Laurens Nov 29 '17 at 12:26 3 ...
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Oracle Differences between NVL and Coalesce

...the first non-NULL (there are some exceptions, such as sequence NEXTVAL): SELECT SUM(val) FROM ( SELECT NVL(1, LENGTH(RAWTOHEX(SYS_GUID()))) AS val FROM dual CONNECT BY level <= 10000 ) This runs for almost 0.5 seconds, since it generates...
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1052: Column 'id' in field list is ambiguous

...and tbl_section which has both the id field in them. How do I go about selecting the id field, because I always get this error: ...
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Insert into … values ( SELECTFROM … )

... Try: INSERT INTO table1 ( column1 ) SELECT col1 FROM table2 This is standard ANSI SQL and should work on any DBMS It definitely works for: Oracle MS SQL Server MySQL Postgres SQLite v3 Teradata DB2 Sybase Vertica HSQLDB H2 AWS RedShift SA...
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Why are Where and Select outperforming just Select?

... Select iterates once over the entire set and, for each item, performs a conditional branch (checking for validity) and a + operation. Where+Select creates an iterator that skips invalid elements (doesn't yield them), perform...
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Is there a way to access the “previous row” value in a SELECT statement?

...d to order by some column for this to be meaningful. Something like this: select t1.value - t2.value from table t1, table t2 where t1.primaryKey = t2.primaryKey - 1 If you know how to order things but not how to get the previous value given the current one (EG, you want to order alphabetically) ...