package sqlite3
Install
Dune Dependency
Authors
Maintainers
Sources
sha256=db9b84db23c25812dad8b56117d6c9473ee1c43ee79bd434356b688fc03e472f
md5=93763885a3606252aa8004f7662dd161
doc/sqlite3/Sqlite3/index.html
Module Sqlite3
Source
API for Sqlite 3.* databases
Exceptions
InternalError reason
is raised when the bindings detect an unknown/unsupported situation.
Error reason
is raised when some SQL operation is called on a nonexistent handle and the functions does not return a return code, or if there is no error code corresponding to this error. Functions returning return codes communicate errors by returning the specific error code.
RangeError (index, maximum)
is raised if some column or bind operation refers to a nonexistent column or binding. The first entry of the returned tuple is the specified index, the second is the limit which was violated.
Types
Database handle. Used to store information regarding open databases and the error code from the last operation if the function implementing that operation takes a database handle as a parameter.
NOTE: database handles are closed (see db_close
) automatically when they are reclaimed by the GC unless they have already been closed earlier by the user. It is good practice to manually close database handles to free resources as quickly as possible.
Compiled statement handle. Stores information about compiled statements created by the prepare
or prepare_tail
functions.
Type of name of a column returned by queries.
Type of row data (with potential NULL-values)
Type of row data (without NULL-values)
Return codes
Column data types
General database operations
val db_open :
?mode:[ `READONLY | `NO_CREATE ] ->
?uri:bool ->
?memory:bool ->
?mutex:[ `NO | `FULL ] ->
?cache:[ `SHARED | `PRIVATE ] ->
?vfs:string ->
string ->
db
db_open ?mode ?uri ?memory ?mutex ?cache ?vfs filename
opens the database file filename
, and returns a database handle.
Special filenames: ":memory:" and "" open an in-memory or temporary database respectively. Behaviour explained here: https://www.sqlite.org/inmemorydb.html
The optional arguments mode
, uri
, memory
and mutex
are only meaningful with SQLite versions >= 3.5, cache
only for versions >= 3.6.18. For older versions an exception will be raised if any of them is set to a non-default value. The database is opened read-only if `READONLY
is passed as mode. The database file will not be created if it is missing and `NO_CREATE
is set. The uri
parameter enables URI filename interpretation and corresponds to SQLITE_OPEN_URI
in the SQLite3 API. The memory
parameter opens an in-memory database and corresponds to SQLITE_OPEN_MEMORY
in the SQLite3 API. mutex
determines how the database is accessed. The mutex parameters `NO
and `FULL
correspond to SQLITE_OPEN_NOMUTEX
and SQLITE_OPEN_FULLMUTEX
in the SQLite3 API respectively. The cache parameters `SHARED
and `PRIVATE
correspond to SQLITE_OPEN_SHAREDCACHE
and SQLITE_OPEN_PRIVATECACHE
in the SQLite3 API respectively.
enable_load_extension db onoff
enable/disable the sqlite3 load extension.
exec db ?cb sql
performs SQL-operation sql
on database db
. If the operation contains query statements, then the callback function cb
will be called for each matching row. The first parameter of the callback is the contents of the row, the second paramater are the headers of the columns associated with the row. Exceptions raised within the callback will abort the execution and escape exec
.
exec_no_headers db ?cb sql
performs SQL-operation sql
on database db
. If the operation contains query statements, then the callback function cb
will be called for each matching row. The parameter of the callback is the contents of the row. Exceptions raised within the callback will abort the execution and escape exec_no_headers
.
exec_not_null db ~cb sql
performs SQL-operation sql
on database db
. If the operation contains query statements, then the callback function cb
will be called for each matching row. The first parameter of the callback is the contents of the row, which must not contain NULL-values, the second paramater are the headers of the columns associated with the row. Exceptions raised within the callback will abort the execution and escape exec_not_null
.
exec_not_null_no_headers db ~cb sql
performs SQL-operation sql
on database db
. If the operation contains query statements, then the callback function cb
will be called for each matching row. The parameter of the callback is the contents of the row, which must not contain NULL-values. Exceptions raised within the callback will abort the execution and escape exec_not_null_no_headers
.
Fine grained query operations
prepare db sql
compile SQL-statement sql
for database db
into bytecode. The statement may be only partially compiled. In this case prepare_tail
can be called on the returned statement to compile the remaining part of the SQL-statement.
NOTE: this really uses the C-function sqlite3_prepare_v2
, i.e. avoids the older, deprecated sqlite3_prepare
-function.
prepare_tail stmt
compile the remaining part of the SQL-statement stmt
to bytecode.
NOTE: this really uses the C-function sqlite3_prepare_v2
, i.e. avoids the older, deprecated sqlite3_prepare
-function.
recompile stmt
recompiles the SQL-statement associated with stmt
to bytecode. The statement may be only partially compiled. In this case prepare_tail
can be called on the statement to compile the remaining part of the SQL-statement. Call this function if the statement expires due to some schema change.
step stmt
performs one step of the query associated with SQL-statement stmt
.
finalize stmt
finalizes the statement stmt
. After finalization, the only valid usage of the statement is to use it in prepare_tail
, or to recompile
it.
reset stmt
resets the statement stmt
, e.g. to restart the query, perhaps with different bindings.
sleep ms
sleeps at least ms
milliseconds.
Data query
Binding data to the query
bind stmt n data
binds the value data
to the free variable at position n
of statement stmt
. NOTE: the first variable has index 1
!
clear_bindings stmt
resets all bindings associated with prepared statement stmt
.
Stepwise query convenience functions
User-defined functions
create_funN db name f
registers function f
under name name
with database handle db
. The function has arity N
.
create_funN db name f
registers function f
under name name
with database handle db
. The function has arity 0
.
create_fun1 db name f
registers function f
under name name
with database handle db
. The function has arity 1
.
create_fun2 db name f
registers function f
under name name
with database handle db
. The function has arity 2
.
create_fun3 db name f
registers function f
under name name
with database handle db
. The function has arity 3
.
delete_function db name
deletes function with name name
from database handle db
.
busy_timeout db ms
sets a busy handler that sleeps for a specified amount of time when a table is locked. The handler will sleep multiple times until at least ms
milliseconds of sleeping have accumulated.