I have made a search form which is showing results successfully from 1 table "links", but I want the results to be searched from multiple tables like "links1" "links2".
This is my coding
$orderby = " ORDER BY id desc";
$sql = "SELECT * FROM links " . $queryCondition;
$result = mysqli_query($conn,$sql);
This is a perfect problem for that UNION SELECT can solve. Say you have two tables, links1 and links2, both with the exact same column names. What you can do in SQL then is SELECT * FROM links1 UNION SELECT * FROM links2 and that will return the data as if both tables were beneath each other. For more info read https://www.w3schools.com/sql/sql_union.asp
Related
I have a table named purchase_details_master and another is sales_detais_master Where all the purchase and sales details are available.
Structure of Purchase Table: These are the data which I have purchased
Structure of Sales Table: These are the data which I have sell
Now I need to show the data like this, This image is showing the iPhone 12 data. In the Inward field showing tha pieces of purchased item, In the Outward field showing the data of sells pieces, and the closing data showing like Opening + Inward or Opening - Outward = Closing
I am using Core Php with Sqlite database
$item = $_POST['item'];
$sql = "SELECT * FROM purchase_details_master WHERE item_id = '$item'";
$sql_run = $conn->query($sql);
I have used while loop it's not solving the problem
Kindly solve this out for me! Thank you in Advance
A JOIN clause is used to combine rows from two or more tables, based on a related column between them.
like that.
SELECT * FROM purchase_details_master AS pdm INNER JOIN sales_detais_master AS sdm ON sdm.item_id = pdm.item_id WHERE sdm.item_id = ?
this will select all fields from the two tables
$sql = "SELECT * FROM purchase_details_master, sales_detais_master WHERE purchase_details_master.item_id = '$item' AND purchase_details_master.item_id = sales_details_master.item_id";
or select exact fields from the two tables
SELECT table1.field1, table1.field2, table2.field1, table2.field3
FROM table1, table2,
WHERE table1.field1 = something, or table1.field1 = table2.field2
Im searching for a function in MySQL in order to Select rows from multiple tables that have a similar name. For example: Proyect_1, Proyect_2, Proyect_3
All of the tables have the same column names, the only difference between the tables is the table name. It starts with the prefix 'proyect'. The issue is that the program doesn´t know how many 'proyect' tables there are, so i can´t make a list of them and select data like always
I need something like this:
SELECT mydata FROM TABLES LIKE 'Proyect_%';
Any ideas? Thanks!
To get all tables with a common prefix
SHOW TABLES LIKE 'Proyect_%';
This will return rows of tables that matched the prefix. Example:
Proyect_1
Proyect_2
Proyect_3
In PHP you can create a UNION query that will pick up the tables returned by the above query,
$sql = "SHOW TABLES LIKE 'Proyect_%'";
$result = $conn->query($sql);
$dataQuery = array();
$query = "";
if ($result->num_rows > 0) {
// output data of each row
while($row = $result->fetch_array(MYSQLI_NUM)) {
$dataQuery[] = "SELECT * FROM {$row[0]}";
}
$query = implode(' UNION ', $dataQuery);
}
echo $query;
if you want to search for all tables with name like Proyect then you can get from MySQL information schema.
SELECT * FROM information_schema.tables
From here you can find table by table name
I have the following two queries. The first query is fetching a key called srNumber from first table called tags and then the second query is using that srNumber to fetch details from a second table called nexttable.
$tagQuery = "SELECT * FROM tags WHERE status = 0 AND currentStage = '1' AND assignedTo = '1' ORDER BY
deliveryDate ASC";
$tagQueryExecute = mysqli_query($conn, $tagQuery);
while($rows = mysqli_fetch_array($tagQueryExecute)){
$srNumber = $rows['srNumber'];
$nextQuery = "SELECT * FROM nexttable WHERE srNumber='$srNumber'";
$nextQueryExecute = mysqli_query($conn, $nextQuery);
$detailsFromNextTable = mysqli_fetch_array($nextQueryExecute);
//Show these details
}
For a small result this is not a big issue. But if the first query got so many results, then second query has to run as many times as number of loop. Is there any other way to do this efficiently?
NB: Please ignore the SQL injection issues with these queries. I just simplified it to show the problem
As you appear to have only 1 row in the second table, you would be better off with a join, MySQL: Quick breakdown of the types of joins gives some more info on the types of joins.
SELECT *
FROM tags t
JOIN nexttable n on t.srNumber = n.srNumber
WHERE t.status = 0 AND t.currentStage = '1' AND t.assignedTo = '1'
ORDER BY t.deliveryDate ASC
This also removes the SQL injection as well.
I would also recommend removing the * and just list the columns you intend to use, this also helps if you have columns with the same names in the different tables as you can add an alias to the specific columns.
FYI - the original problem you have is similar to What is the "N+1 selects problem" in ORM (Object-Relational Mapping)?
I need help to create an SQL query in order to SUM the values of specific column from all tables LIKE table_% as the tables will grow over time and this must cater for new table names based on the format below
Scheme Name: database_01
Table Names: tb_data_'YEAR'_'MONTH'
YEAR and MONTH are both values which range from all 12 months and years from 2011 to 2018.
Each Table contains a column called TOTAL_VALUE. I have a php script that triggers an SQL query to pull data from the database.
I would like to SUM the total of each tables TOTAL_VALUE column and save the value for my script below to push the array.
$sql = "SELECT TOTAL_VALUES FROM tb_data_2017_october";
$result = mysqli_query($conn, $sql);
$data = array(); while($enr = mysqli_fetch_assoc($result)){
$a = array($enr['TOTAL_VALUES']);
foreach ($a as $as){
echo "'".$as."', ";}
array_push($data, $as); }
I have been trying to alter the SQL with options such as:
SELECT id FROM table1
UNION
SELECT id FROM table2
UNION
SELECT id FROM table3
UNION
SELECT id FROM table4
However i need to cater for the ability to check all tables that are like tb_data_%
See this question for information about getting the list of tables: Get table names using SELECT statement in MySQL
You can get the list of tables in one query result, and then query each table. I'll rework your code slightly to give an example:
// Get the tables
$tables_sql = "SELECT table_name
FROM information_schema.tables
WHERE table_schema='<your DB>'
AND table_name LIKE 'tb_data%'";
$tables = mysqli_query($conn, $sql);
// Iterate over the tables
while($table = mysqli_fetch_assoc($tables)){
{
/*
* Your code
*/
// This query assumes that you can trust your table names not to to an SQL injection
$sql = "SELECT TOTAL_VALUES FROM " . $table['table_name'];
$result = mysqli_query($conn, $sql);
$data = array(); while($enr = mysqli_fetch_assoc($result)){
$a = array($enr['TOTAL_VALUES']);
foreach ($a as $as){
echo "'".$as."', ";
array_push($data, $as); }
}
You can do whatever you need once your have your list of tables. You can build one big union query (which would be more efficient than querying each table individually), or feed the tables to the MERGE engine, as in barmar's answer
Use the MERGE storage engine to create a virtual table that combines all the monthly tables.
CREATE TABLE tb_all_data (
...
) ENGINE=MERGE UNION=(tb_data_2017_october, tb_data_2017_november, ...);
List all the tables in the UNION= list, and update it whenever you create a new table.
Then you can just query from tb_all_data.
Try this- it will loop through all the tables with the pattern you want and create sums for you:
declare #table table (rowid int identity, name varchar(max))
insert #table
select name from sys.tables where name like '%yourname%'
declare #holding table (name varchar(max), sumvalue int)
declare #iterator int = 1
declare #tablename varchar(max)
while #iterator<=(select max(rowid) from #table)
begin
select #tablename=name from #table where rowid=#iterator
insert #holding
exec('select '+#tablename+' sum(TOTAL_VALUE)TOTAL_VALUE from '+#tablename+' group by +'+#tablename+'')
set #iterator=#iterator+1
end
select * from #holding
I'm developing a website using HTML, PHP and MySQL to access a database. On one page I present a table with data from that database. This is some of the code I'm using:
$sql1 = "SELECT * FROM MyTable ORDER BY ID ASC";
$rs1 = mysqli_query($link,$sql1);
(...)
while($row1 = mysqli_fetch_assoc($rs1)) {
echo "<tr><td>".$row1['ID']."</td><td>".$row1['Field1']."</td><td></td><td>".$row1['Field2']."</td><td>".$row1['Field3']."</td></tr>\n" ;
}
Notice the empty <td></td>? That's because I want to have there the number of time a given ID appears on two other tables (there are foreign keys involved, obviously). I have sorted out the code I need for that:
$sql2 = "SELECT (SELECT COUNT(*) FROM MyTable2 WHERE ID2=$row1['ID'])+(SELECT COUNT(*) FROM MyTable3 WHERE ID2=$row1['ID']) AS total";
However, I'm struggling with figuring out a way to add this result to the other table. Any help?
try with this.. it inserts the total to an table after selecting the count.
"INSERT INTO total_table (total)
SELECT (SELECT COUNT(*) FROM MyTable2 WHERE ID2=$row1['ID'])+(SELECT COUNT(*) FROM MyTable3 WHERE ID2=$row1['ID']) AS total
WHERE cid = 2"