Without formally scripting a Stored Procedure, this is as good as it is going to get. The SELECT will let you see the generated SQL WHERE table_schema=DATABASE() AND table_name='foo' AND column_name IN Here is the Dynamic SQL to generate the same query USE mydbĬONCAT('SELECT ',column_name,' AS name FROM ',table_name) For this example, let's suppose the following If the intent is to select some columns and generate a single column list of the distinct values, then Dynamic SQL is needed to produce such a query. This would produce a distinct list of names. Nothing could be more elegant that using UNION SELECT her_name AS name FROM foo In this instance, what makes UNION an absolute must is the merging of three columns into a single column. : Calculating values from three related tables, without using join or union.Wildcards are used in conjunction with the LIKE comparison operator or with the NOT LIKE comparison operator. Others have submitted answers trying aggregation to collect data without using UNION What are MySQL Wildcards MySQL Wildcards are characters that help search data matching complex criteria. Where one of the dictionary views: SELECT The LIKE operator allows us to specify one or more parameters. Any related records can be logically evaluated using the SQL LIKE operator. (SELECT := 0) r, INFORMATION_SCHEMA.COLUMNS t Updated JIntroduction to SQL Like with Multiple Values The following article provides an outline for SQL Like with Multiple Values. Using a constant expression: select 1 line for mysql you need use concat ('', field, '') for oracle you need use '' insteaf of '+' Share Improve this answer Follow answered at 8:11 Michael Pakhantsov 24.8k 6 60 59 Add a comment 4 You can construct a pattern from the substring: select a.aa, b.bb from TableA a inner join TableB b on b.bb like '' + a. Using an auxiliary table: create table aux(line int) Of course there are different ways to create a table containing the three rows with values 1,2,3: Pivot Query: select elt(aux.line,foo.his_name,foo.her_name,foo.other_name) all_name Insert into foo(his_name,her_name,other_name) values ('four','five','six') Insert into foo(his_name,her_name,other_name) values ('one','two','three') MySQL 5.6 Schema Setup: create table foo ( Instead the ELT function one can use IF or CASE. Each query row can be filled by the appropriate data. Now we have three rows in our query for each row in the base table foo. We want to create 3 rows for each row of the foo table, so we create an auxiliary table containing three rowsĪnd (cross) join it to the foo table. So MySQL does not have such an "elegant" way to unpivot a table.Ī way to do such unpivoting without the use of UNION can be done buy using a join. So if table_references equals foo the query cannot contains more rows than the table foo. Neither the WHERE, GROUP BY, HAVING, LIMIT, SELECT, INTO, FOR UPDATE nor the LOCK IN SHARE MODE clause can increase the number of rows defined by the FROM clause. This is the syntax diagram of the select statement To fetch fields with multiple values, use LIKE with OR in MySQL select from yourTableName where yourColumnName like ‘AnyStringValue’ or yourColumnName like ‘AnyStringValue’ or yourColumnName like ‘AnyStringValue’. Oracle you can use the following statement to make columns to rows it should retrieve and echo all the Records(rows) which contains all the keywords in a single row on the top of the page and then records which matches Two fields and One field.It is unclear to me what is a "more elegant way". I want to have a multiple search function. I have created a Simple search for my database.the search form contains a drop down menu of the field names and user select the field name and input the keyword and then Click on search to retrieve matching records from that particular field.Įcho "Number of records found: ".$num_results."" Įcho htmlspecialchars(stripslashes($row))
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