4200 (HTTP) :User: `
**Native PostgreSQL, psql** ``` postgresql://
4200 (HTTP) :User: `crate` :Pass: (empty) ::: :::{grid-item} :columns: 8 :margin: 0 :padding: 0 :class: driver-slim **Connection-string examples**
**Native PostgreSQL, psql** ``` postgresql://crate@localhost:5432/doc ``` **JDBC: PostgreSQL pgJDBC** ``` jdbc:crate://crate@localhost:5432/doc ``` **JDBC: CrateDB JDBC, e.g. Apache Flink** ``` jdbc:crate://
If you or your company would like to sponsor node-postgres stop by [GitHub Sponsors](https://github.com/sponsors/brianc) and sign up or feel free to [email me](mailto:brian@pecanware.com) if you want to add your logo to the documentation or discuss higher tiers of sponsorship!
# Version compatibility
node-postgres strives to be compatible with all recent LTS versions of node & the most recent "stable" version. At the time of this writing node-postgres is compatible with node 18.x, 20.x, 22.x, and 24.x.
## Getting started
The simplest possible way to connect, query, and disconnect is with async/await:
```js
import { Client } from 'pg'
const client = new Client()
await client.connect()
const res = await client.query('SELECT $1::text as message', ['Hello world!'])
console.log(res.rows[0].message) // Hello world!
await client.end()
```
### Error Handling
For the sake of simplicity, these docs will assume that the methods are successful. In real life use, make sure to properly handle errors thrown in the methods. A `try/catch` block is a great way to do so:
```ts
import { Client } from 'pg'
const client = new Client()
await client.connect()
try {
const res = await client.query('SELECT $1::text as message', ['Hello world!'])
console.log(res.rows[0].message) // Hello world!
} catch (err) {
console.error(err);
} finally {
await client.end()
}
```
### Pooling
In most applications you'll wannt to use a [connection pool](/features/pooling) to manage your connections. This is a more advanced topic, but here's a simple example of how to use it:
```js
import { Pool } from 'pg'
const pool = new Pool()
const res = await pool.query('SELECT $1::text as message', ['Hello world!'])
console.log(res.rows[0].message) // Hello world!
```
Our real-world apps are almost always more complicated than that, and I urge you to read on!
psqlODBC Configuration Options
Advanced Options 1/3 Dialog Box
- DEFAULTS: Press to this button restore the normal defaults for the
settings described below.
- Recognize Unique Indexes:
Check this option.
- Use Declare/Fetch: If
true, the driver automatically uses declare cursor/fetch to handle
SELECT statements and keeps 100 rows in a cache. This is mostly a
great advantage, especially if you are only interested in reading and not
updating. It results in the driver not sucking down lots of memory
to buffer the entire result set. If set to false, cursors will not
be used and the driver will retrieve the entire result set. For very
large tables, this is very inefficient and may use up all the Windows memory/resources.
However, it may handle updates better since the tables are not kept open,
as they are when using cursors. This was the style of the old podbc32
driver. However, the behavior of the memory allocation is much improved
so even when not using cursors, performance should at least be better than
the old podbc32.
- CommLog (C:\psqlodbc_xxxx.log):
Log communications to/from the backend to that file. This is good
for debugging problems.
- Parse Statements: Tell the driver how to gather the information
about result columns of queries, if the application requests that information
before executing the query. See also ServerSide Prepare options.
The driver checks this option first. If disabled then it checks the Server Side Prepare option.
If this option is enabled, the driver will parse an SQL query statement to identify the columns and tables and gather statistics about them such as precision, nullability, aliases, etc. It then reports this information in SQLDescribeCol, SQLColAttributes, and SQLNumResultCols.
When this option is disabled (the default), the query is sent to the server to be parsed and described. If the parser can not deal with a column (because it is a function or expression, etc.), it will fall back to describing the statement in the server. The parser is fairly sophisticated and can handle many things such as column and table aliases, quoted identifiers, literals, joins, cross-products, etc. It can correctly identify a function or expression column, regardless of the complexity, but it does not attempt to determine the data type or precision of these columns.
- Ignore Timeout:
Ignore SQL_ATTR_QUERY_TIMEOUT set using SQLSetStmtAttr(). Some tools issue SQLSetStmtAttr(.., SQL_ATTR_QUERY_TIMEOUT, ...) internally and sometimes it's difficult for users to change the value.
- MyLog (C:\mylog_xxxx.log):
Log debug messages to that file. This is good
for debugging problems with the driver.
- Unknown Sizes: This controls
what SQLDescribeCol and SQLColAttributes will return as to precision for
character data types (varchar, text, and unknown) in a result set when
the precision is unknown. This was more of a workaround for pre-6.4
versions of PostgreSQL not being able to return the defined column width
of the varchar data type.
- Maximum: Always return the maximum precision of the data type.
- Dont Know: Return "Don't Know" value and let application decide.
- Longest: Return the longest string length of the column of any row. Beware of this setting when using cursors because the cache size may not be a good representation of the longest column in the cache.
MS Access: Seems to handle Maximum setting ok, as well as all the others.
Borland: If sizes are large and lots of columns, Borland may crash badly (it doesn't seem to handle memory allocation well) if using Maximum size.
- Data Type Options: affects how some data types are mapped:
- Text as LongVarChar: PostgreSQL TEXT type is mapped to SQLLongVarchar, otherwise SQLVarchar.
- Unknowns as LongVarChar: Unknown types (arrays, etc) are mapped to SQLLongVarChar, otherwise SQLVarchar
- Bools as Char: Bools are mapped to SQL_CHAR, otherwise to SQL_BIT.
- Max Varchar The maximum
precision of the Varchar and BPChar(char[x]) types. The default is 254
which actually means 255 because of the null terminator. Note, if
you set this value higher than 254, Access will not let you index on varchar
columns!
- Cache Size:When using
cursors, this is the row size of the tuple cache and the default is 100 rows.
If not using cursors, this has no meaning.
- Max LongVarChar: The maximum
precision of the LongVarChar type. The default is 4094 which actually
means 4095 with the null terminator. You can even specify (-4) for
this size, which is the odbc SQL_NO_TOTAL value.
- SysTable Prefixes: Additional prefixes of table names to regard
as System Tables. Tables that begin with "pg_" are always treated as system
tables, even without this option. Separate each prefix with a semicolon
(;)
- Batch Size:Chunk size when executing batches with arrays of
parameters. Setting 1 to this option forces one by one execution (the
behavior before).
Advanced Options 2/3 Dialog Box
- ReadOnly: Whether the
datasource will allow updates.
- Show System Tables: The
driver will treat system tables as regular tables in SQLTables. This
is good for Access so you can see system tables.
- LF <-> CR/LF conversion: Convert Unix style line endings to
DOS style.
- Updateable Cursors: Enable updateable cursor emulation in the
driver.
- Bytea as LO: Allow the use of bytea columns for Large Objects.
- Row Versioning: Allows
applications to detect whether data has been modified by other users while
you are attempting to update a row. It also speeds the update process
since every single column does not need to be specified in the where clause
to update a row. The driver uses the "xmin" system field of PostgreSQL
to allow for row versioning. Microsoft products seem to use this
option well. See the faq
for details on what you need to do to your database to allow for the row
versioning feature to be used.
- Display Optional Error Message: Display optional(detail, hint, statement position etc) error messages.
- True is -1: Represent TRUE as -1 for compatibility with some applications.
- Server side prepare:If set, the driver uses server-side prepared
statements. See also Parse Statement option. Note that if a query
needs to be described before execution, e.g. because the application calls
SQLDescribeCol() or SQLNumResultCols() before SQLExecute(), the driver will
send a Parse request to the server even if this option is disabled. In that
case, the query that is sent to the server for parsing will have the
parameter markers replaced with the actual parameter values, or NULL literals
if the values are not known yet.
- Int8 As: Define what datatype to report int8 columns as.
- Numeric As: Specify the map from numeric items without precision to SQL data types. numeric(default), varchar, double or memo(SQL_LONGVARCHAR) can be specified.
- Extra Opts: combination of the following bits.
0x1: Force the output of short-length formatted connection string. Check this bit when you use MFC CDatabase class.
0x2: Fake MS SQL Server so that MS Access recognizes PostgreSQL's serial type as AutoNumber type.
0x4: Reply ANSI (not Unicode) char types for the inquiries from applications. Try to check this bit when your applications don't seem to be good at handling Unicode data.
- Level of rollback on errors: Specifies what to rollback should an
error occur.
- Nop(0): Don't rollback anything and let the application handle the
error.
- Transaction(1): Rollback the entire transaction.
- Statement(2): Rollback the statement.
Setup note: This specification is set up with the PROTOCOL option parameter.
PROTOCOL=7.4-(0|1|2)
default value is Statement (it is Transaction for servers before 8.0).
- Nop(0): Don't rollback anything and let the application handle the
error.
- OID Options:
- Show Column: Includes the OID
in SQLColumns. This is good for using as a unique identifier to update
records if no good key exists OR if the key has many parts, which
blows up the backend.
- Fake Index: This option
fakes a unique index on OID. This is useful when there is not a real
unique index on OID and for apps which can't ask what the unique identifier
should be (i.e, Access 2.0).
- Show Column: Includes the OID
in SQLColumns. This is good for using as a unique identifier to update
records if no good key exists OR if the key has many parts, which
blows up the backend.
- Connect Settings: The
driver sends these commands to the backend upon a successful connection.
It sends these settings AFTER it sends the driver "Connect Settings".
Use a semi-colon (;) to separate commands. This can now handle any
query, even if it returns results. The results will be thrown away
however!
- TCP KEEPALIVE setting(by sec): Specifies TCP keepalives setting.
- disable: Check when client-side TCP keepalives are not used.
- idle time: The number of seconds of inactivity after which TCP should send a keepalive message to the server.
- interval: The number of seconds after which a TCP keepalive message that is not acknowledged by the server should be retransmitted.
- disable: Check when client-side TCP keepalives are not used.
Advanced Options 3/3 Dialog Box
- Allow connections urecoverable by MSDTC?: How to test distributed transactions.
- yes: MSDTC is needless unless applications crash. So don't check the connectivity from MSDTC.
- rejects sslmode verify-[ca|full]: reject ssl connections with verify-ca or verify-full mode because in those cases msdtc could hardly establish the connection.
- no: First confirm the connectivity from MSDTC.
- Libpq parameters: Specify libpq connection parameters with conninfo
style strings e.g. sslrootcert=c:\\myfolder\\myroot sslcert=C:\\myfolder\\mycert sslkey=C:\\myfolder\\mykey.
Though host, port, dbname, user, password, sslmode, keepalives_idle or keepalive_interval parameters can be set using this(pqopt) option, the use is not recommended because they are ordinarily set by other options. When some settings for those parameters conflict with other ordinary options, connections are rejected.
Global settings Dialog Box
This dialog allows you to specify pre-connection/default logging options
- CommLog (C:\psqlodbc_xxxx.log - Communications log):
Log communications to/from the backend to that file. This is good
for debugging problems.
- MyLog (C:\mylog_xxxx.log - Detailed debug output):
Log debug messages to that file. This is good
for debugging problems with the driver.
- MSDTCLog (C:\pgdtclog\mylog_xxxx.log - MSDTC debug output):
Log debug messages to that file. This is good
for debugging problems with the MSDTC.
- Specification of the holder for log outputs:
Adjustment of write permission.
Manage DSN Dialog Box
This dialog allows you to select which PostgreSQL ODBC driver to use for this connection. Note that this may not work with third party drivers.
How to specify as a connection option
There is a method of specifying a connection option in a keyword strings.
Example:VBA
-
myConn = "ODBC;DRIVER={PostgreSQL Unicode};" & serverConn & _
"A0=0;A1=7.4;A2=0;A3=0;A4=0;A5=0;A6=;A7=100;A8=4096;A9=0;" & _
"B0=254;B1=8190;B2=0;B3=0;B4=1;B5=1;B6=0;B7=1;B8=0;B9=1;BI=-5;" & _
"C0=0;C2=dd_;C4=1;C5=1;C6=1;C7=1;C8=1;C9=0;CA=verify-full;D1=30;D4=40;" & _
"D5={sslrootcert=C:\\myfolder\\myroot sslcert=C:\\myfolder\\mycert sslkey=C:\\myfolder\\mykey}"
Please refer to a keyword list for details.