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I'd like to get all of a mysql table's col names into an array in php?
Is there a query for this?
The best way is to use the INFORMATION_SCHEMA metadata virtual database. Specifically the INFORMATION_SCHEMA.COLUMNS table...
SELECT `COLUMN_NAME`
FROM `INFORMATION_SCHEMA`.`COLUMNS`
WHERE `TABLE_SCHEMA`='yourdatabasename'
AND `TABLE_NAME`='yourtablename';
It's VERY powerful, and can give you TONS of information without need to parse text (Such as column type, whether the column is nullable, max column size, character set, etc)...
Oh, and it's standard SQL (Whereas SHOW ... is a MySQL specific extension)...
For more information about the difference between SHOW... and using the INFORMATION_SCHEMA tables, check out the MySQL Documentation on INFORMATION_SCHEMA in general...
You can use the following query for MYSQL:
SHOW `columns` FROM `your-table`;
Below is the example code which shows How to implement above syntax in php to list the names of columns:
$sql = "SHOW COLUMNS FROM your-table";
$result = mysqli_query($conn,$sql);
while($row = mysqli_fetch_array($result)){
echo $row['Field']."<br>";
}
For Details about output of SHOW COLUMNS FROM TABLE visit: MySQL Refrence.
Seems there are 2 ways:
DESCRIBE `tablename`
or
SHOW COLUMNS FROM `tablename`
More on DESCRIBE here: http://dev.mysql.com/doc/refman/5.0/en/describe.html
I have done this in the past.
SELECT column_name
FROM information_schema.columns
WHERE table_name='insert table name here';
Edit: Today I learned the better way of doing this. Please see ircmaxell's answer.
Parse the output of SHOW COLUMNS FROM table;
Here's more about it here: http://dev.mysql.com/doc/refman/5.0/en/show-columns.html
Use mysql_fetch_field() to view all column data. See manual.
$query = 'select * from myfield';
$result = mysql_query($query);
$i = 0;
while ($i < mysql_num_fields($result))
{
$fld = mysql_fetch_field($result, $i);
$myarray[]=$fld->name;
$i = $i + 1;
}
"Warning
This extension is deprecated as of PHP 5.5.0, and will be removed in the future."
The simplest solution out of all Answers:
DESC `table name`
or
DESCRIBE `table name`
or
SHOW COLUMNS FROM `table name`
An old PHP function "mysql_list_fields()" is deprecated. So, today the best way to get names of fields is a query "SHOW COLUMNS FROM table_name [LIKE 'name']". So, here is a little example:
$fields = array();
$res=mysql_query("SHOW COLUMNS FROM mytable");
while ($x = mysql_fetch_assoc($res)){
$fields[] = $x['Field'];
}
foreach ($fields as $f) { echo "<br>Field name: ".$f; }
when you want to check your all table structure with some filed then use this code. In this query i select column_name,column_type and table_name for more details . I use order by column_type so i can see it easily.
SELECT `COLUMN_NAME`,COLUMN_TYPE,TABLE_NAME
FROM `INFORMATION_SCHEMA`.`COLUMNS`
WHERE `TABLE_SCHEMA`='yourdatabasename' order by DATA_TYPE;
If you want to check only double type filed then you can do it easily
SELECT `COLUMN_NAME`,COLUMN_TYPE,TABLE_NAME,DATA_TYPE
FROM `INFORMATION_SCHEMA`.`COLUMNS`
WHERE `TABLE_SCHEMA`='yourdatabasename' AND DATA_TYPE like '%bigint%' order by DATA_TYPE;
if you want to check which field allow null type etc then you can use this
SELECT `COLUMN_NAME`,COLUMN_TYPE,TABLE_NAME,IS_NULLABLE,DATA_TYPE
FROM `INFORMATION_SCHEMA`.`COLUMNS`
WHERE `TABLE_SCHEMA`='yourdatabasename' and DATA_TYPE like '%bigint%' and IS_NULLABLE ='NO' order by COLUMN_TYPE;
you want to check more then thik link also help you.
https://dev.mysql.com/doc/refman/5.7/en/columns-table.html
this generates a string of column names with a comma delimiter:
SELECT CONCAT('(',GROUP_CONCAT(`COLUMN_NAME`),')')
FROM `INFORMATION_SCHEMA`.`COLUMNS`
WHERE `TABLE_SCHEMA`='database_name'
AND `TABLE_NAME`='table_name';
function get_col_names(){
$sql = "SHOW COLUMNS FROM tableName";
$result = mysql_query($sql);
while($record = mysql_fetch_array($result)){
$fields[] = $record['0'];
}
foreach ($fields as $value){
echo 'column name is : '.$value.'-';
}
}
return get_col_names();
Not sure if this is what you were looking for, but this worked for me:
$query = query("DESC YourTable");
$col_names = array_column($query, 'Field');
That returns a simple array of the column names / variable names in your table or array as strings, which is what I needed to dynamically build MySQL queries. My frustration was that I simply don't know how to index arrays in PHP very well, so I wasn't sure what to do with the results from DESC or SHOW. Hope my answer is helpful to beginners like myself!
To check result: print_r($col_names);
SHOW COLUMNS in mysql 5.1 (not 5.5) uses a temporary disk table.
http://dev.mysql.com/doc/refman/5.1/en/internal-temporary-tables.html
http://dev.mysql.com/doc/refman/5.1/en/show-columns.html
So it can be considered slow for some cases. At least, it can bump up your created_tmp_disk_tables value. Imagine one temporary disk table per connection or per each page request.
SHOW COLUMNS is not really so slow, possibly because it uses file system cache. Phpmyadmin says ~0.5ms consistently. This is nothing compared to 500ms-1000ms of serving a wordpress page. But still, there are times it matters. There is a disk system involvement, you never know what happens when server is busy, cache is full, hdd is stalled etc.
Retrieving column names through SELECT * FROM ... LIMIT 1 was around ~0.1ms, and it can use query cache as well.
So here is my little optimized code to get column names from a table, without using show columns if possible:
function db_columns_ar($table)
{
//returns Array('col1name'=>'col1name','col2name'=>'col2name',...)
if(!$table) return Array();
if(!is_string($table)) return Array();
global $db_columns_ar_cache;
if(!empty($db_columns_ar_cache[$table]))
return $db_columns_ar_cache[$table];
//IMPORTANT show columns creates a temp disk table
$cols=Array();
$row=db_row_ar($q1="SELECT * FROM `$table` LIMIT 1");
if($row)
{
foreach($row as $name=>$val)
$cols[$name]=$name;
}
else
{
$coldata=db_rows($q2="SHOW COLUMNS FROM `$table`");
if($coldata)
foreach($coldata as $row)
$cols[$row->Field]=$row->Field;
}
$db_columns_ar_cache[$table]=$cols;
//debugexit($q1,$q2,$row,$coldata,$cols);
return $cols;
}
Notes:
As long as your tables first row does not contain megabyte range of data, it should work fine.
The function names db_rows and db_row_ar should be replaced with your specific database setup.
IN WORDPRESS:
global $wpdb; $table_name=$wpdb->prefix.'posts';
foreach ( $wpdb->get_col( "DESC " . $table_name, 0 ) as $column_name ) {
var_dump( $column_name );
}
Try this one out I personally use it:
SHOW COLUMNS FROM $table where field REGEXP 'stock_id|drug_name'
This question is old, but I got here looking for a way to find a given query its field names in a dynamic way (not necessarily only the fields of a table). And since people keep pointing this as the answer for that given task in other related questions, I'm sharing the way I found it can be done, using Gavin Simpson's tips:
//Function to generate a HTML table from a SQL query
function myTable($obConn,$sql)
{
$rsResult = mysqli_query($obConn, $sql) or die(mysqli_error($obConn));
if(mysqli_num_rows($rsResult)>0)
{
//We start with header. >>>Here we retrieve the field names<<<
echo "<table width=\"100%\" border=\"0\" cellspacing=\"2\" cellpadding=\"0\"><tr align=\"center\" bgcolor=\"#CCCCCC\">";
$i = 0;
while ($i < mysqli_num_fields($rsResult)){
$field = mysqli_fetch_field_direct($rsResult, $i);
$fieldName=$field->name;
echo "<td><strong>$fieldName</strong></td>";
$i = $i + 1;
}
echo "</tr>";
//>>>Field names retrieved<<<
//We dump info
$bolWhite=true;
while ($row = mysqli_fetch_assoc($rsResult)) {
echo $bolWhite ? "<tr bgcolor=\"#CCCCCC\">" : "<tr bgcolor=\"#FFF\">";
$bolWhite=!$bolWhite;
foreach($row as $data) {
echo "<td>$data</td>";
}
echo "</tr>";
}
echo "</table>";
}
}
This can be easily modded to insert the field names in an array.
Using a simple: $sql="SELECT * FROM myTable LIMIT 1" can give you the fields of any table, without needing to use SHOW COLUMNS or any extra php module, if needed (removing the data dump part).
Hopefully this helps someone else.
if you use php, use this gist.
it can get select fields full info with no result，and all custom fields such as:
SELECT a.name aname, b.name bname, b.*
FROM table1 a LEFT JOIN table2 b
ON a.id = b.pid;
if above sql return no data,will also get the field names aname, bname, b's other field name
just two line:
$query_info = mysqli_query($link, $data_source);
$fetch_fields_result = $query_info->fetch_fields();
This query fetches a list of all columns in a database without having to specify a table name. It returns a list of only column names:
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_schema = 'db_name'
However, when I ran this query in phpmyadmin, it displayed a series of errors. Nonetheless, it worked. So use it with caution.
if you only need the field names and types (perhaps for easy copy-pasting into Excel):
SELECT COLUMN_NAME, DATA_TYPE
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA='databasenamegoeshere'
AND DATA_TYPE='decimal' and TABLE_NAME = 'tablenamegoeshere'
remove
DATA_TYPE='decimal'
if you want all data types
i no expert, but this works for me..
$sql = "desc MyTable";
$result = #mysql_query($sql);
while($row = #mysql_fetch_array($result)){
echo $row[0]."<br>"; // returns the first column of array. in this case Field
// the below code will return a full array-> Field,Type,Null,Key,Default,Extra
// for ($c=0;$c<sizeof($row);$c++){echo #$row[$c]."<br>";}
}
I have tried this query in SQL Server and this worked for me :
SELECT name FROM sys.columns WHERE OBJECT_ID = OBJECT_ID('table_name')
The call of DESCRIBE is working fine to get all columns of a table but if you need to filter on it, you need to use the SHOW COLUMNS FROM instead.
Example of PHP function to get all info of a table :
// get table columns (or return false if table not found)
function get_table_columns($db, $table) {
global $pdo;
if($cols = $pdo->query("DESCRIBE `$db`.`$table`")) {
if($cols = $cols->fetchAll(PDO::FETCH_ASSOC)) {
return $cols;
}
}
return false;
}
In my case, I had to find the primary key of a table. So, I used :
SHOW COLUMNS FROM `table` WHERE `Key`='PRI';
Here is my PHP function :
// get table Primary Key
function get_table_pk($db, $table) {
global $pdo;
$q = "SHOW COLUMNS FROM `$db`.`$table` WHERE `Key` = 'PRI'";
if($cols = $pdo->query($q)) {
if($cols = $cols->fetchAll(PDO::FETCH_ASSOC)) {
return $cols[0];
}
}
return false;
}
I want to find Mysql columns of a table in PHP.
This is my code but it does not work as expected:
while($row3 = mysql_fetch_array($query3))
{
foreach($row3 as $column => $data)
{
echo'<td>'.$column.'</td>';
}
}
The table columns in the database are ID, User and Pass.
But the output is 0 ID 1 User 2 Pass
You can use DESCRIBE:
DESCRIBE my_table;
Or in newer versions you can use INFORMATION_SCHEMA:
SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'my_database' AND TABLE_NAME = 'my_table';
Or you can use SHOW COLUMNS:
SHOW COLUMNS FROM my_table;
while ($row = mysql_fetch_assoc($result))
use this.
Change mysql_fetch_array($query) to mysql_fetch_assoc($query).
It will give array of column name as a key and column's value as value.
I have a table that has multiple columns, the column names can be changed in the future, and rather than my script select from the columns by their name (since that info can change), is there a way to select by column position?
For example, I want to select the second column in the table... can I do that easily?
I understand the reasons not to do this, but I still want to.
Easy solution? Just SELECT * FROM table, fetch with $row = mysql_fetch_row() and read from $row[1], it will be the content of the "second column" in order (as it starts in 0).
If you want it a little bit more professional and select only whats needed, you can get the second column name from the INFORMATION_SCHEMA using a query like this:
SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'your database schema' AND TABLE_NAME = 'the wanted table name' AND ORDINAL_POSITION = 2;
But if you really want to do this the right way then know where you put your nose. If the table structure is changed and your code needs adaptations because of it, so be it. This is how it should be done. If you leave it "working" but relying in potentially wrong information it may cause much bigger problems to you later.
This is such a bad idea that I almost don't want to give you a solution, but it is possible. MySQL has a database named information_schema that stores DDL data that you can query. What you are after would be COLUMNS.ORDINAL_POSITION.
SELECT COLUMN_NAME FROM information_schema.COLUMNS
WHERE TABLE_NAME = ? AND ORDINAL_POSITION = ?
This will give you the name of the nth column, which you can use in the field list of a subsequent query. It would not make sense to do this in a single query.
The following three exampels shows you how to print the 3rd column using MySQL, MySQLi and PDO.
MySQL
while ($row = mysql_fetch_array($query)) {
print $row[2];
}
MySQLi
$sth->execute();
$sth->bind_result($var1, $var2, $var3);
while ($sth->fetch()) {
print $var3;
}
PDO
$sth->execute();
while ($row = $sth->fetchAll()) {
print $row[2];
}
In PHP you can execute query using $res = mysql_fetch_row($query). then you can fetch second column by $res[1];
I have had such problem many days ago. But I found the solution:
$conn = new mysqli("localhost", "root", "", "Mybase");
$result = $conn->query("SELECT * FROM imagesbase");
$outp = "";
while($rs = $result->fetch_array(MYSQLI_BOTH)) {`
$outp .= "Picture: ".$rs[0]." ".$rs["ImgPathName"]."";`
}
$conn->close();
echo "$outp";
This code may be changed by column number or column name. MYSQLI_BOTH , MYSQLI_NUM or MYSQLI_ASSOC are used for this.
I can't seem to find or write a sqlquery that SELECTS the DEFAULT VALUE
(and I don't think I can generate it in phpmyadmin for me to copy)
I tried to SELECT it as if it was a record but to no avail...
$defaultValue_find = mysql_query(
"SELECT $group FROM grouptable WHERE $group='DEFAULT'")
or die("Query failed:".mysql_error());
$defaultValue_fetch = mysql_fetch_row($defaultValue_find);
$defaultValue = $defaultValue_fetch[0];
echo $defaultValue;
"SELECT $group FROM grouptable WHERE $group=DEFAULT( $group ) "
Or I think better:
"SELECT DEFAULT( $group ) FROM grouptable LIMIT 1 "
Update - correction
As #Jeff Caron pointed, the above will only work if there is at least 1 row in grouptable. If you want the result even if the grouptable has no rows, you can use this:
"SELECT DEFAULT( $group )
FROM (SELECT 1) AS dummy
LEFT JOIN grouptable
ON True
LIMIT 1 ;"
Get the default values of all fields in mytable in the associative array $res:
// MySQL v.5.7+
$res = [];
$sql = "SHOW FULL COLUMNS FROM `mytable`";
foreach ($PDO->query( $sql, PDO::FETCH_ASSOC ) as $row) {
$res[$row['Field']] = $row['Default'] ;
}
print_r($res);
You can get the default column of any table, and in fact lots of interesting information about it, by looking at the INFORMATION_SCHEMA.COLUMNS tables. As the documentation states...
INFORMATION_SCHEMA provides access to database metadata, information about the MySQL server such as the name of a database or table, the data type of a column, or access privileges. (Source: MySQL 8.0 Reference Manual / INFORMATION_SCHEMA Tables / Introduction.)
So, to get the column default, just SELECT COLUMN_DEFAULT, like...
SELECT COLUMN_DEFAULT
FROM information_schema.columns
WHERE TABLE_SCHEMA = 'YourSchema'
AND TABLE_NAME = 'YourTable' AND
COLUMN_NAME = 'YourField';
You can then just wrap this into a subquery, SELECT * FROM YourTable WHERE YourField = (queryabove). This lets you make a much more customizable, default-based list in your MySQL query.
I'd like to get all of a mysql table's col names into an array in php?
Is there a query for this?
The best way is to use the INFORMATION_SCHEMA metadata virtual database. Specifically the INFORMATION_SCHEMA.COLUMNS table...
SELECT `COLUMN_NAME`
FROM `INFORMATION_SCHEMA`.`COLUMNS`
WHERE `TABLE_SCHEMA`='yourdatabasename'
AND `TABLE_NAME`='yourtablename';
It's VERY powerful, and can give you TONS of information without need to parse text (Such as column type, whether the column is nullable, max column size, character set, etc)...
Oh, and it's standard SQL (Whereas SHOW ... is a MySQL specific extension)...
For more information about the difference between SHOW... and using the INFORMATION_SCHEMA tables, check out the MySQL Documentation on INFORMATION_SCHEMA in general...
You can use the following query for MYSQL:
SHOW `columns` FROM `your-table`;
Below is the example code which shows How to implement above syntax in php to list the names of columns:
$sql = "SHOW COLUMNS FROM your-table";
$result = mysqli_query($conn,$sql);
while($row = mysqli_fetch_array($result)){
echo $row['Field']."<br>";
}
For Details about output of SHOW COLUMNS FROM TABLE visit: MySQL Refrence.
Seems there are 2 ways:
DESCRIBE `tablename`
or
SHOW COLUMNS FROM `tablename`
More on DESCRIBE here: http://dev.mysql.com/doc/refman/5.0/en/describe.html
I have done this in the past.
SELECT column_name
FROM information_schema.columns
WHERE table_name='insert table name here';
Edit: Today I learned the better way of doing this. Please see ircmaxell's answer.
Parse the output of SHOW COLUMNS FROM table;
Here's more about it here: http://dev.mysql.com/doc/refman/5.0/en/show-columns.html
Use mysql_fetch_field() to view all column data. See manual.
$query = 'select * from myfield';
$result = mysql_query($query);
$i = 0;
while ($i < mysql_num_fields($result))
{
$fld = mysql_fetch_field($result, $i);
$myarray[]=$fld->name;
$i = $i + 1;
}
"Warning
This extension is deprecated as of PHP 5.5.0, and will be removed in the future."
The simplest solution out of all Answers:
DESC `table name`
or
DESCRIBE `table name`
or
SHOW COLUMNS FROM `table name`
An old PHP function "mysql_list_fields()" is deprecated. So, today the best way to get names of fields is a query "SHOW COLUMNS FROM table_name [LIKE 'name']". So, here is a little example:
$fields = array();
$res=mysql_query("SHOW COLUMNS FROM mytable");
while ($x = mysql_fetch_assoc($res)){
$fields[] = $x['Field'];
}
foreach ($fields as $f) { echo "<br>Field name: ".$f; }
when you want to check your all table structure with some filed then use this code. In this query i select column_name,column_type and table_name for more details . I use order by column_type so i can see it easily.
SELECT `COLUMN_NAME`,COLUMN_TYPE,TABLE_NAME
FROM `INFORMATION_SCHEMA`.`COLUMNS`
WHERE `TABLE_SCHEMA`='yourdatabasename' order by DATA_TYPE;
If you want to check only double type filed then you can do it easily
SELECT `COLUMN_NAME`,COLUMN_TYPE,TABLE_NAME,DATA_TYPE
FROM `INFORMATION_SCHEMA`.`COLUMNS`
WHERE `TABLE_SCHEMA`='yourdatabasename' AND DATA_TYPE like '%bigint%' order by DATA_TYPE;
if you want to check which field allow null type etc then you can use this
SELECT `COLUMN_NAME`,COLUMN_TYPE,TABLE_NAME,IS_NULLABLE,DATA_TYPE
FROM `INFORMATION_SCHEMA`.`COLUMNS`
WHERE `TABLE_SCHEMA`='yourdatabasename' and DATA_TYPE like '%bigint%' and IS_NULLABLE ='NO' order by COLUMN_TYPE;
you want to check more then thik link also help you.
https://dev.mysql.com/doc/refman/5.7/en/columns-table.html
this generates a string of column names with a comma delimiter:
SELECT CONCAT('(',GROUP_CONCAT(`COLUMN_NAME`),')')
FROM `INFORMATION_SCHEMA`.`COLUMNS`
WHERE `TABLE_SCHEMA`='database_name'
AND `TABLE_NAME`='table_name';
function get_col_names(){
$sql = "SHOW COLUMNS FROM tableName";
$result = mysql_query($sql);
while($record = mysql_fetch_array($result)){
$fields[] = $record['0'];
}
foreach ($fields as $value){
echo 'column name is : '.$value.'-';
}
}
return get_col_names();
Not sure if this is what you were looking for, but this worked for me:
$query = query("DESC YourTable");
$col_names = array_column($query, 'Field');
That returns a simple array of the column names / variable names in your table or array as strings, which is what I needed to dynamically build MySQL queries. My frustration was that I simply don't know how to index arrays in PHP very well, so I wasn't sure what to do with the results from DESC or SHOW. Hope my answer is helpful to beginners like myself!
To check result: print_r($col_names);
SHOW COLUMNS in mysql 5.1 (not 5.5) uses a temporary disk table.
http://dev.mysql.com/doc/refman/5.1/en/internal-temporary-tables.html
http://dev.mysql.com/doc/refman/5.1/en/show-columns.html
So it can be considered slow for some cases. At least, it can bump up your created_tmp_disk_tables value. Imagine one temporary disk table per connection or per each page request.
SHOW COLUMNS is not really so slow, possibly because it uses file system cache. Phpmyadmin says ~0.5ms consistently. This is nothing compared to 500ms-1000ms of serving a wordpress page. But still, there are times it matters. There is a disk system involvement, you never know what happens when server is busy, cache is full, hdd is stalled etc.
Retrieving column names through SELECT * FROM ... LIMIT 1 was around ~0.1ms, and it can use query cache as well.
So here is my little optimized code to get column names from a table, without using show columns if possible:
function db_columns_ar($table)
{
//returns Array('col1name'=>'col1name','col2name'=>'col2name',...)
if(!$table) return Array();
if(!is_string($table)) return Array();
global $db_columns_ar_cache;
if(!empty($db_columns_ar_cache[$table]))
return $db_columns_ar_cache[$table];
//IMPORTANT show columns creates a temp disk table
$cols=Array();
$row=db_row_ar($q1="SELECT * FROM `$table` LIMIT 1");
if($row)
{
foreach($row as $name=>$val)
$cols[$name]=$name;
}
else
{
$coldata=db_rows($q2="SHOW COLUMNS FROM `$table`");
if($coldata)
foreach($coldata as $row)
$cols[$row->Field]=$row->Field;
}
$db_columns_ar_cache[$table]=$cols;
//debugexit($q1,$q2,$row,$coldata,$cols);
return $cols;
}
Notes:
As long as your tables first row does not contain megabyte range of data, it should work fine.
The function names db_rows and db_row_ar should be replaced with your specific database setup.
IN WORDPRESS:
global $wpdb; $table_name=$wpdb->prefix.'posts';
foreach ( $wpdb->get_col( "DESC " . $table_name, 0 ) as $column_name ) {
var_dump( $column_name );
}
Try this one out I personally use it:
SHOW COLUMNS FROM $table where field REGEXP 'stock_id|drug_name'
This question is old, but I got here looking for a way to find a given query its field names in a dynamic way (not necessarily only the fields of a table). And since people keep pointing this as the answer for that given task in other related questions, I'm sharing the way I found it can be done, using Gavin Simpson's tips:
//Function to generate a HTML table from a SQL query
function myTable($obConn,$sql)
{
$rsResult = mysqli_query($obConn, $sql) or die(mysqli_error($obConn));
if(mysqli_num_rows($rsResult)>0)
{
//We start with header. >>>Here we retrieve the field names<<<
echo "<table width=\"100%\" border=\"0\" cellspacing=\"2\" cellpadding=\"0\"><tr align=\"center\" bgcolor=\"#CCCCCC\">";
$i = 0;
while ($i < mysqli_num_fields($rsResult)){
$field = mysqli_fetch_field_direct($rsResult, $i);
$fieldName=$field->name;
echo "<td><strong>$fieldName</strong></td>";
$i = $i + 1;
}
echo "</tr>";
//>>>Field names retrieved<<<
//We dump info
$bolWhite=true;
while ($row = mysqli_fetch_assoc($rsResult)) {
echo $bolWhite ? "<tr bgcolor=\"#CCCCCC\">" : "<tr bgcolor=\"#FFF\">";
$bolWhite=!$bolWhite;
foreach($row as $data) {
echo "<td>$data</td>";
}
echo "</tr>";
}
echo "</table>";
}
}
This can be easily modded to insert the field names in an array.
Using a simple: $sql="SELECT * FROM myTable LIMIT 1" can give you the fields of any table, without needing to use SHOW COLUMNS or any extra php module, if needed (removing the data dump part).
Hopefully this helps someone else.
if you use php, use this gist.
it can get select fields full info with no result，and all custom fields such as:
SELECT a.name aname, b.name bname, b.*
FROM table1 a LEFT JOIN table2 b
ON a.id = b.pid;
if above sql return no data,will also get the field names aname, bname, b's other field name
just two line:
$query_info = mysqli_query($link, $data_source);
$fetch_fields_result = $query_info->fetch_fields();
This query fetches a list of all columns in a database without having to specify a table name. It returns a list of only column names:
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_schema = 'db_name'
However, when I ran this query in phpmyadmin, it displayed a series of errors. Nonetheless, it worked. So use it with caution.
if you only need the field names and types (perhaps for easy copy-pasting into Excel):
SELECT COLUMN_NAME, DATA_TYPE
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA='databasenamegoeshere'
AND DATA_TYPE='decimal' and TABLE_NAME = 'tablenamegoeshere'
remove
DATA_TYPE='decimal'
if you want all data types
i no expert, but this works for me..
$sql = "desc MyTable";
$result = #mysql_query($sql);
while($row = #mysql_fetch_array($result)){
echo $row[0]."<br>"; // returns the first column of array. in this case Field
// the below code will return a full array-> Field,Type,Null,Key,Default,Extra
// for ($c=0;$c<sizeof($row);$c++){echo #$row[$c]."<br>";}
}
I have tried this query in SQL Server and this worked for me :
SELECT name FROM sys.columns WHERE OBJECT_ID = OBJECT_ID('table_name')
The call of DESCRIBE is working fine to get all columns of a table but if you need to filter on it, you need to use the SHOW COLUMNS FROM instead.
Example of PHP function to get all info of a table :
// get table columns (or return false if table not found)
function get_table_columns($db, $table) {
global $pdo;
if($cols = $pdo->query("DESCRIBE `$db`.`$table`")) {
if($cols = $cols->fetchAll(PDO::FETCH_ASSOC)) {
return $cols;
}
}
return false;
}
In my case, I had to find the primary key of a table. So, I used :
SHOW COLUMNS FROM `table` WHERE `Key`='PRI';
Here is my PHP function :
// get table Primary Key
function get_table_pk($db, $table) {
global $pdo;
$q = "SHOW COLUMNS FROM `$db`.`$table` WHERE `Key` = 'PRI'";
if($cols = $pdo->query($q)) {
if($cols = $cols->fetchAll(PDO::FETCH_ASSOC)) {
return $cols[0];
}
}
return false;
}